Active perturbation-based online performance supervision method and system for new energy power station

Abstract

Disclosed in the present invention are an active perturbation-based online performance supervision method and system for new energy power stations. The method comprises: in a set supervision period, performing active perturbation tests on the performance of a new energy power station, so as to analyze constraint parameters of short-time signals and continuous weak signals; extracting a short-time signal checking data set and a continuous weak signal checking data set; acquiring feedback parameters of a short-time signal injection test and feedback parameters of a continuous weak signal injection test, so as to obtain test feedback performance evaluation indicators of the new energy power station; and performing comprehensive evaluation warning feedback of the performance of the new energy power station. The present invention can timely and effectively capture the dynamic response performances of new energy power stations, thus improving the robustness of performance evaluation for new energy power stations; the present invention can also perform comprehensive evaluation on the performance optimization of new energy power stations, and efficiently identify the potential performance problems and bottlenecks of new energy power stations, thereby greatly improving the reliability of emergency response processing for new energy power stations.

Description

A method and system for online monitoring of new energy station performance based on active disturbance Technical Field

[0001] The present invention relates to the technical field of new energy station performance supervision, and in particular to a method and system for online supervision of new energy station performance based on active disturbance. Background Art

[0002] New energy sites usually include a variety of power generation equipment such as solar power stations and wind farms, involving complex power systems. In addition, the operating environment of new energy sites may be affected by factors such as season and weather, resulting in fluctuations in power output. In order to ensure the operating efficiency and operational reliability of new energy sites, it is necessary to continuously monitor the performance of new energy sites in order to promptly discover potential safety risks and ensure that the sites can continue to operate in a safe and stable state, thereby further optimizing power generation and improving the power generation efficiency of new energy sites.

[0003] Existing technology, such as the invention patent application with announcement number CN113162028B, discloses a method for evaluating the comprehensive performance of AGC of new energy stations based on RankBoost, which includes the following steps: obtaining historical output data of new energy stations and establishing a valid data set V; calculating the frequency regulation performance index of the new energy stations in each control cycle based on the valid data set V; calculating the index set I of Nd new energy stations under M control cycles, and processing the index set I to obtain the effective index set S of new energy AGC; based on the effective index set S of new energy AGC, using RankBoost to evaluate the comprehensive performance of new energy AGC new energy stations. This invention can be applied to the evaluation of new energy AGC new energy stations with different installed capacities, different regions and different frequency regulation performance, and can provide a useful reference for the operation control of new energy participating in the secondary frequency regulation of the power system and the distribution of benefits in the auxiliary frequency regulation market. Based on the above scheme, it is found that the current performance evaluation of new energy stations rarely injects disturbance signals with different characteristics in a targeted manner to conduct specific performance evaluation of new energy stations. The lack of characteristic disturbance signal testing may lead to the inability to timely and effectively capture the dynamic response performance of new energy stations, limit the robustness evaluation of the performance of new energy stations, make it impossible to conduct a comprehensive evaluation of the performance optimization of new energy stations, and make it difficult to efficiently identify potential performance problems and bottlenecks of new energy stations, thereby reducing the response and processing reliability of new energy stations in emergency situations. Summary of the Invention

[0004] The purpose of this section is to summarize some aspects of the embodiments of the present invention and briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section and the abstract and title of this application to avoid obscuring the purpose of this section, the abstract and the title of the invention, and such simplifications or omissions should not be used to limit the scope of the present invention.

[0005] In view of the above existing problems, the present invention is proposed. Therefore, the present invention provides a new energy station performance online monitoring method based on active disturbance to solve the above problems.

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

[0007] In a first aspect, the present invention provides a method for online monitoring of new energy station performance based on active disturbance, comprising:

[0008] Conduct active performance disturbance tests on new energy stations during the set regulatory cycle, including short-term signal injection tests and continuous weak signal injection tests, and analyze the constraint parameters of short-term signals and continuous weak signals in turn;

[0009] Extracting a short-term signal verification data set and a continuous weak signal verification data set according to the constraint parameters of the short-term signal and the continuous weak signal;

[0010] Collect feedback parameters of the short-term signal injection test and the continuous weak signal injection test of the new energy station, and obtain test feedback performance evaluation indicators of the new energy station based on the short-term signal calibration data set and the continuous weak signal calibration data set;

[0011] Based on the test feedback performance evaluation indicators of the new energy station, a comprehensive performance evaluation warning feedback of the new energy station is carried out.

[0012] As a preferred solution of the online monitoring method for new energy station performance based on active disturbance described in the present invention, the constraint parameters for analyzing short-term signals and continuous weak signals include:

[0013] Conduct short-term signal injection tests on new energy stations during the set regulatory cycle and obtain the injected short-term signal data, including the short-term signal release intensity and short-term signal waveform;

[0014] Extracting short-time signal waveform element information from the short-time signal waveform diagram, including short-time signal pulse width, short-time signal pulse duration, peak amplitude, peak point rise time, and peak point fall time;

[0015] Performing numerical processing and analysis based on the short-time signal release intensity and short-time signal waveform element information to obtain constraint parameters of the short-time signal;

[0016] Conduct continuous weak signal injection tests on new energy stations during the set regulatory cycle and obtain the injected continuous weak signal data, including the average release intensity of the continuous weak signal and the continuous weak signal waveform;

[0017] Extracting continuous weak signal waveform element information according to the continuous weak signal waveform graph, including continuous weak signal average pulse width, single pulse average duration, pulse number and pulse frequency;

[0018] According to the average release intensity of the continuous weak signal and the waveform element information of the continuous weak signal, the constraint parameters of the continuous weak signal are obtained through numerical analysis.

[0019] As a preferred solution of the online monitoring method for new energy station performance based on active disturbance described in the present invention, extracting a short-term signal verification data set and a continuous weak signal verification data set includes:

[0020] According to the constraint parameters of the short-time signal, matching is performed with the calibration data sets corresponding to the short-time signal in each constraint parameter interval stored in the data warehouse to obtain the corresponding short-time signal calibration data set;

[0021] According to the constraint parameters of the continuous weak signal, the continuous weak signal is matched with the calibration data set corresponding to each constraint parameter interval stored in the data warehouse to obtain the corresponding continuous weak signal calibration data set.

[0022] As a preferred solution of the method for online monitoring of new energy station performance based on active disturbance according to the present invention, the feedback parameters collected during the short-time signal injection test include:

[0023] In the short-time signal injection test, the feedback verification point pre-deployed on the high-voltage side of the grid connection point is marked as the grid connection high-voltage feedback verification point;

[0024] Statistics are collected on the response parameters of the grid-connected high-voltage feedback verification point during the short-time signal injection test, which are marked as short-time signal injection test feedback parameters.

[0025] As a preferred solution of the method for online monitoring of new energy station performance based on active disturbance according to the present invention, the feedback parameters collected during the continuous weak signal injection test include:

[0026] In the continuous weak signal injection test, the feedback verification points deployed on the grid-connected low-voltage side and the central line are marked as grid-connected low-voltage feedback verification points and central line feedback verification points;

[0027] Recording a period corresponding to the duration of the continuous weak signal injection test as a continuous weak signal test cycle, monitoring and extracting the current output waveform and the voltage output waveform of the grid-connected low-voltage feedback verification point and the centralized line feedback verification point during the continuous weak signal test cycle;

[0028] Collect the time difference of the AGC and AVC adjustment response intervals set at the grid connection point as the first element of continuous weak signal feedback;

[0029] Dividing the continuous weak signal test period into a plurality of weak signal test moments according to the current output waveform and the voltage output waveform of the grid-connected low-voltage feedback check point and the central line feedback check point, and calculating the current difference and voltage difference between the grid-connected low-voltage feedback check point and the central line feedback check point at the weak signal test moment as the second continuous weak signal feedback element;

[0030] The current output waveform and the voltage output waveform of the grid-connected low-voltage feedback verification point are subjected to waveform fitting processing, and the waveform obtained by fitting is used as the weak current test electrical characteristic waveform of the grid-connected low-voltage feedback verification point, and the weak current test electrical characteristic waveform of the line-collecting feedback verification point is obtained by synchronous fitting;

[0031] According to the low-voltage side weak current test electrical characteristic reference calibration waveform in the continuous weak signal calibration data set, the weak current test electrical characteristic waveform of the grid-connected low-voltage feedback calibration point is compared and processed, and the total offset length and the maximum length of a single offset of the weak current test electrical characteristic waveform of the grid-connected low-voltage feedback calibration point are extracted and used as the continuous weak signal feedback element three;

[0032] According to the weak current test electrical characteristic reference calibration waveform at the collection line in the continuous weak signal calibration data set, the weak current test electrical characteristic waveform at the collection line feedback calibration point is compared and processed, and the total offset length and the maximum length of a single offset of the weak current test electrical characteristic waveform at the collection line feedback calibration point are extracted and used as the continuous weak signal feedback element four;

[0033] According to the weak current test electrical characteristic waveforms of the grid-connected low-voltage feedback check point and the centralized line feedback check point, the peak density and the trough density of the weak current test electrical characteristic waveforms of the grid-connected low-voltage feedback check point and the centralized line feedback check point are sequentially extracted as the continuous weak signal feedback element five;

[0034] The continuous weak signal feedback elements one, two, three, four and five are combined as the continuous weak signal injection test feedback parameters.

[0035] As a preferred solution of the online monitoring method for new energy station performance based on active disturbance according to the present invention, the test feedback performance evaluation index is obtained as follows:

[0036]

[0037] in, It represents the test feedback performance evaluation index of the new energy station. 、 They represent the short-term signal injection test feedback calibration index coefficient and the continuous weak signal injection test feedback calibration index coefficient of the new energy station respectively. 、 They represent the weighting factors for setting the short-time signal injection test feedback calibration index coefficient and the continuous weak signal injection test feedback calibration index coefficient, respectively. Indicates the initial reference evaluation index of the preset test feedback performance.

[0038] As a preferred solution of the method for online monitoring of new energy station performance based on active disturbance according to the present invention, the comprehensive performance evaluation warning feedback includes:

[0039] Obtain the grid-connected power output of the new energy stations during the supervision cycle, and import the evaluation and warning model based on the performance evaluation indicators of the test feedback of the new energy stations, which can be expressed as:

[0040]

[0041] in, It represents the test feedback performance evaluation index of the new energy station. Indicates the final constraint indicator for reference of preset test feedback performance evaluation. Indicates the amount of power generated by new energy stations during the regulatory cycle. Indicates the reference constraint index for pre-loss reduction evaluation corresponding to the preset unit output on-grid capacity;

[0042] Obtain comprehensive performance evaluation warning feedback results of new energy stations and conduct evaluation warning feedback.

[0043] In a second aspect, the present invention provides an online monitoring system for new energy station performance based on active disturbance, comprising:

[0044] The performance active perturbation test module is used to perform active perturbation tests on new energy stations during a set regulatory cycle, including short-term signal injection tests and continuous weak signal injection tests, and analyze the constraint parameters of short-term signals and continuous weak signals in turn;

[0045] A performance verification data set extraction module is used to extract a short-term signal verification data set and a continuous weak signal verification data set according to the constraint parameters of the short-term signal and the continuous weak signal;

[0046] A station performance feedback parameter collection and processing module is used to collect feedback parameters of the short-term signal injection test and the continuous weak signal injection test of the new energy station, and obtain the test feedback performance evaluation index of the new energy station based on the short-term signal calibration data set and the continuous weak signal calibration data set;

[0047] The supervision feedback module is used to provide a comprehensive performance evaluation warning feedback of the new energy station based on the test feedback performance evaluation indicators of the new energy station.

[0048] In a third aspect, the present invention provides an electronic device, comprising:

[0049] memory and processor;

[0050] The memory is used to store computer-executable instructions, and the processor is used to execute the computer-executable instructions. When the computer-executable instructions are executed by the processor, the steps of the online supervision method of new energy station performance based on active disturbance are implemented.

[0051] In a fourth aspect, the present invention provides a computer-readable storage medium storing computer-executable instructions, which, when executed by a processor, implement the steps of the method for online supervision of new energy station performance based on active disturbance.

[0052] Compared with the prior art, the present invention has the following beneficial effects: the present invention can perform short-time signal injection tests and continuous weak signal injection tests on new energy stations in a set supervision cycle, and conduct comprehensive performance evaluation and warning feedback on new energy stations, breaking through the current limitations caused by the rare targeted injection of disturbance signals with different characteristics to conduct specific performance evaluations on new energy stations. By performing short-time signal injection tests and continuous weak signal injection tests on new energy stations and conducting targeted data analysis, the dynamic response performance of new energy stations can be captured in a timely and effective manner, the robustness of the performance evaluation of new energy stations is improved, and a comprehensive performance optimization evaluation of new energy stations can be conducted, and potential performance problems and bottlenecks of new energy stations can be efficiently identified, thereby greatly improving the response and processing reliability of new energy stations in emergency situations. By analyzing short-time signals and continuous weak signal injection tests, the present invention can perform comprehensive performance evaluations on new energy stations and effectively identify potential performance problems and bottlenecks of new energy stations. The constraint parameters of the continuous weak signal are measured, and the short-term signal calibration data set and the continuous weak signal calibration data set are extracted. By matching and screening the corresponding calibration data set according to the characteristics of the test signal, the reliability, accuracy and test efficiency of the new energy station performance test can be improved, and the mutual adaptability and matching between the new energy station test and calibration data are further increased, ensuring the full and effective utilization of the new energy station test data; by comprehensively processing the short-term signal injection test feedback parameters and the continuous weak signal injection test feedback parameters of the new energy station, the test feedback performance evaluation index of the new energy station is obtained, which can fully evaluate the operation reliability of the new energy station, and then ensure the operational safety of the new energy station, reduce the operation safety risks caused by performance failures, help to help the new energy station to make reasonable adjustments and improvements, and improve the overall performance operation level. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. Those skilled in the art can also derive other drawings based on these drawings without inventive effort. Among them:

[0054] FIG1 is a schematic diagram of the overall process of a method for online monitoring of new energy station performance based on active disturbance according to an embodiment of the present invention;

[0055] FIG2 is a module diagram of an online monitoring system for new energy station performance based on active disturbance according to an embodiment of the present invention. DETAILED DESCRIPTION

[0056] To make the above-mentioned objects, features, and advantages of the present invention more clearly understood, the following detailed description of the specific embodiments of the present invention is given in conjunction with the accompanying drawings. It is obvious that the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary persons in this field without creative work should fall within the scope of protection of the present invention.

[0057] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. 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.

[0058] Secondly, the term "one embodiment" or "embodiment" herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in various places throughout this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive of other embodiments.

[0059] The present invention is described in detail with reference to schematic diagrams. For ease of illustration, cross-sectional views of device structures may be partially enlarged and not to scale when describing embodiments of the present invention. Furthermore, the schematic diagrams are merely illustrative and should not limit the scope of the present invention. Furthermore, in actual production, the three-dimensional dimensions of length, width, and depth should be included.

[0060] In the description of the present invention, it should be noted that the terms "upper, lower, inner, and outer" and other references to orientations or positional relationships are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely to facilitate and simplify the description of the present invention. They are not intended to indicate or imply that the devices or components referred to must have, be constructed, or operate in a specific orientation, and therefore should not be construed as limitations on the present invention. Furthermore, the terms "first, second, or third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0061] In this disclosure, unless otherwise specified or limited, the terms "mounted," "connected," and "connected" should be interpreted broadly. For example, they may refer to fixed, removable, or integral connections. They may also refer to mechanical, electrical, or direct connections, indirect connections through an intermediary, or internal communication between two components. Those skilled in the art will understand the specific meanings of these terms in this disclosure.

[0062] Example 1

[0063] 1-2 , an embodiment of the present invention provides an online monitoring method for new energy station performance based on active disturbance, as shown in FIG1 , including:

[0064] S100: Perform active performance disturbance tests on new energy stations during a set regulatory cycle, including short-term signal injection tests and continuous weak signal injection tests, and analyze the constraint parameters of short-term signals and continuous weak signals in turn;

[0065] Furthermore, the short-term signal constraint parameters analyzed include:

[0066] Conduct short-term signal injection tests on new energy stations during the set regulatory cycle and obtain the injected short-term signal data, including the short-term signal release intensity and short-term signal waveform;

[0067] Extracting short-time signal waveform element information from the short-time signal waveform diagram, including short-time signal pulse width, short-time signal pulse duration, peak amplitude, peak point rise time, and peak point fall time;

[0068] According to the short-time signal release intensity and the short-time signal waveform element information, numerical processing and analysis are performed to obtain the constraint parameters of the short-time signal.

[0069] Specifically, the specific execution constraints of the constraint parameters of the short-term signal are:

[0070]

[0071] in, is the constraint parameter of the short-time signal, is the short-term signal release intensity, 、 、 、 、 The short-time signal waveform element information is the short-time signal pulse width, short-time signal pulse duration, peak amplitude, peak point rise time and peak point fall time. 、 They are respectively the preset reference short-time signal strength and short-time signal pulse width, 、 are the constraint parameter evaluation factors for the preset short-time signal pulse unit duration and unit peak amplitude, 、 The peak point of the preset short-time signal defines the proportion of the rising time and the peak point defines the proportion of the falling time. It is the correction coefficient of the constraint parameter of the preset short-time signal.

[0072] It should be noted that by analyzing the constraint parameters of the short-time signal, based on the short-time signal strength and the short-time signal waveform element information, the characteristic information of the short-time signal can be fully quantitatively analyzed, providing data support for the analysis and extraction of the short-time signal calibration data set, and facilitating more accurate data processing.

[0073] The constraint parameters for analyzing continuous weak signals include:

[0074] Conduct continuous weak signal injection tests on new energy stations during the set regulatory cycle and obtain the injected continuous weak signal data, including the average release intensity of the continuous weak signal and the continuous weak signal waveform;

[0075] Extracting continuous weak signal waveform element information according to the continuous weak signal waveform graph, including continuous weak signal average pulse width, single pulse average duration, pulse number and pulse frequency;

[0076] According to the average release intensity of the continuous weak signal and the waveform element information of the continuous weak signal, the constraint parameters of the continuous weak signal are obtained through numerical analysis.

[0077] Specifically, the specific execution constraints of the constraint parameters of the continuous weak signal are:

[0078]

[0079] in, is the constraint parameter of continuous weak signal, 、 are the average release intensity of continuous weak signals and the average pulse width of continuous weak signals, 、 The preset reference continuous weak signal strength and reference continuous weak signal pulse width are respectively, and are the average duration of a single pulse and the number of pulses, 、 The unit duration corresponding to a single pulse of a preset continuous weak signal and the constraint parameter evaluation factor of a single pulse are respectively: and They are pulse frequency and preset reference pulse frequency, is the correction coefficient of the constraint parameter for the preset continuous weak signal.

[0080] It should be noted that by analyzing the constraint parameters of the continuous weak signal and extracting the continuous weak signal waveform element information from the continuous weak signal waveform diagram, the characteristic information of the continuous weak signal can be fully analyzed, and then the corresponding continuous weak signal strength and relative quality during the continuous weak signal injection test can be determined, providing data support for the subsequent analysis and extraction of the continuous weak signal calibration data set.

[0081] Specifically, the constraint parameters of short-time signals and continuous weak signals, wherein the constraint parameters of short-time signals are specifically obtained by processing the short-time signal strength and short-time signal waveform element information, and the results of numerical analysis processing of the injected short-time signal are used as the basis for analysis and extraction of the short-time signal calibration data set.

[0082] The constraint parameters of the continuous weak signal are specifically obtained by processing the average release intensity of the continuous weak signal and the continuous weak signal waveform element information, and the results of numerical analysis of the injected continuous weak signal are used as the basis for analysis and extraction of the continuous weak signal calibration data set.

[0083] S200, extracting a short-term signal calibration data set and a continuous weak signal calibration data set according to the constraint parameters of the short-term signal and the continuous weak signal;

[0084] It should be noted that by analyzing the constraint parameters of short-time signals and continuous weak signals, and extracting short-time signal calibration data sets and continuous weak signal calibration data sets, and by matching and screening the corresponding calibration data sets according to the characteristics of the test signals, the reliability, accuracy and test efficiency of the new energy station performance test can be improved, and the mutual adaptability and matching between the new energy station test and calibration data can be further increased, ensuring the full and effective utilization of the new energy station test data.

[0085] Furthermore, extracting a short-term signal calibration data set and a continuous weak signal calibration data set includes:

[0086] According to the constraint parameters of the short-time signal, the calibration data sets corresponding to the short-time signals in each constraint parameter interval stored in the supervision data warehouse are matched to obtain the corresponding short-time signal calibration data sets, including the reference transient response voltage, reference transient response current, reference instantaneous active power, reference instantaneous reactive power and reference steady-state recovery intermittent time difference on the high-voltage side of the grid connection point;

[0087] According to the constraint parameters of the continuous weak signal, the calibration data sets corresponding to the continuous weak signals in each constraint parameter interval stored in the regulatory data warehouse are matched to obtain the corresponding continuous weak signal calibration data sets, including the defined time difference of the regulation response of AGC and AVC at the collection line, the defined current mutual difference and the defined voltage mutual difference between the grid-connected low-voltage side and the collection line, the reference calibration waveform of the weak current test electrical characteristics on the low-voltage side and the reference calibration waveform of the weak current test electrical characteristics at the collection line, and the defined offset length of the weak current test electrical characteristics waveform on the grid-connected low-voltage side and the collection line, and the defined peak density definition deviation and trough density definition deviation of the weak current test electrical characteristics waveform between the grid-connected low-voltage side and the collection line.

[0088] S300, collecting feedback parameters of a short-term signal injection test and a continuous weak signal injection test of the new energy station, and obtaining a test feedback performance evaluation index of the new energy station based on the short-term signal calibration data set and the continuous weak signal calibration data set;

[0089] It should be noted that by comprehensively processing the short-term signal injection test feedback parameters and continuous weak signal injection test feedback parameters of the new energy station, the test feedback performance evaluation index of the new energy station is obtained, which can fully evaluate the operational reliability of the new energy station, and then ensure the operational safety of the new energy station, reduce the operational safety risks caused by performance failures, and help the new energy station to make reasonable adjustments and improvements, and improve the overall performance operation level.

[0090] Specifically, collecting the feedback parameters of the short-time signal injection test includes:

[0091] In the short-time signal injection test, the feedback verification point pre-deployed on the high-voltage side of the grid connection point is marked as the grid connection high-voltage feedback verification point;

[0092] Statistics are collected on the response parameters of the grid-connected high-voltage feedback verification point during the short-time signal injection test, which are marked as short-time signal injection test feedback parameters. These parameters include transient response voltage, transient response current, instantaneous active power, instantaneous reactive power, and steady-state recovery intermittent time difference. The steady-state recovery intermittent time difference is the time consumed by the grid-connected high-voltage feedback verification point to stabilize the recovery value during the short-time signal injection test.

[0093] It should be noted that the high-voltage side of the new energy station grid connection point is specifically: when the new energy station is connected to the grid, the place where it is connected to the main grid of the power system is usually called the grid connection point, and the high-voltage side refers to the high-voltage side of the connection point in the power system, that is, the high-voltage cable or equipment that connects the station to the power grid.

[0094] The transient response voltage and transient response current are the voltage and current of the instantaneous response of the grid-connected high-voltage feedback verification point during the short-time signal injection test. The instantaneous active power and instantaneous reactive power are: the instantaneous active power represents the power actually used to do work at the grid-connected high-voltage feedback verification point during the short-time signal injection test; the instantaneous reactive power represents the power not doing work caused by capacitance or inductance at the grid-connected high-voltage feedback verification point during the short-time signal injection test, which is usually expressed as the phase difference between current and voltage.

[0095] Furthermore, based on the short-time signal injection test feedback parameters and analysis of the short-time signal injection test feedback verification index coefficients of the new energy station, the specific execution constraints are expressed as follows:

[0096]

[0097] in, 、 、 、 、 It represents the transient response voltage, transient response current, instantaneous active power, instantaneous reactive power and steady-state recovery intermittent time difference of the grid-connected high-voltage feedback verification point during the short-time signal injection test. 、 、 、 、 They are the reference transient response voltage, reference transient response current, reference instantaneous active power, reference instantaneous reactive power and reference steady-state recovery intermittent time difference on the high-voltage side of the grid connection point, respectively. e is a natural constant.

[0098] Furthermore, collecting feedback parameters of the continuous weak signal injection test includes:

[0099] In the continuous weak signal injection test, the feedback verification points deployed on the grid-connected low-voltage side and the central line are marked as grid-connected low-voltage feedback verification points and central line feedback verification points;

[0100] The period corresponding to the continuous weak signal injection test duration is recorded as a continuous weak signal test cycle, and the current output waveform and the voltage output waveform of the grid-connected low-voltage feedback verification point and the centralized line feedback verification point during the continuous weak signal test cycle are monitored and extracted, wherein the current output waveform has time as the horizontal axis and the current value as the vertical axis, and the voltage output waveform has time as the horizontal axis and the voltage value as the vertical axis;

[0101] It should be noted that the low-voltage side and the collection point of the new energy station grid are the low-voltage side, which refers to the lower voltage level in the electrical system inside the new energy station. On the low-voltage side of the new energy station grid, some work such as electric energy regulation, protection and distribution will be carried out to ensure the transmission and utilization of electric energy in the station. The collection point refers to the place where the new energy station is connected to the main grid of the power system, usually inside the station, and is used to connect to the high-voltage side of the main grid of the power system.

[0102] Collect the time difference of AGC and AVC adjustment response interval set at the grid connection point, and record them as 、 , as the continuous weak signal feedback element one;

[0103] It should be noted that the AGC and AVC installed at the grid-connected line of the new energy station are common control systems in the power system of the new energy station. AGC is an automatic power generation control system, which is usually used to adjust the output power of the generator in the station power system to maintain the frequency of the station power system within an appropriate range. The AGC installed at the grid-connected line of the new energy station can automatically adjust the output power of the generator of the station to cope with the fluctuation of the frequency in the station power system during the active disturbance test. AVC is an automatic voltage control system, which is usually used to adjust the voltage in the power system to ensure that it is within the normal operating range. The AVC installed at the grid-connected line of the new energy station can automatically adjust the voltage of the station to maintain the stability and reliability of the station power system.

[0104] The AGC and AVC set at the grid-connected line of the new energy station help to ensure the coordinated operation of the new energy station, while improving the stability and responsiveness of the station's power system, which is very important for the smooth operation of the entire power grid. The present invention analyzes the time difference of the AGC and AVC adjustment response interval to further improve the depth and specificity of the analysis of the new energy station.

[0105] According to the AGC and AVC adjustment response interval time difference set at the grid-connected line of the new energy station, the first indicator factor of the continuous weak signal injection test feedback verification is obtained. The specific execution constraints are:

[0106]

[0107] in, Feedback verification of the first indicator factor for continuous weak signal injection test, 、 They are the AGC and AVC adjustment response interval time difference set at the grid connection point of the new energy station. 、 Define the time difference for the regulation response of AGC and AVC at the hub, respectively, 、 They are the correction coefficients of AGC and AVC at the preset collection point respectively.

[0108] Further, according to the current output waveform and voltage output waveform of the grid-connected low-voltage feedback check point and the central line feedback check point, the continuous weak signal test period is divided into multiple weak signal test moments, and the current mutual difference and voltage mutual difference between the grid-connected low-voltage feedback check point and the central line feedback check point at the weak signal test moment are counted as the continuous weak signal feedback element two;

[0109] According to the continuous weak signal feedback element 2, the second indicator factor of the continuous weak signal injection test feedback verification is obtained. The specific execution constraints are:

[0110]

[0111] in, Feedback verification of the second indicator factor for continuous weak signal injection test, 、 are the current mutual difference and voltage mutual difference between the grid-connected low-voltage feedback check point and the centralized line feedback check point at the jth weak signal test moment, 、 They are the defined current difference and voltage difference between the low-voltage side of the grid and the collection point, 、 They are the correction coefficients for the preset current mutual difference and voltage mutual difference, is the number of each weak signal test moment, , is the total number of weak signal test moments.

[0112] Furthermore, the current output waveform and the voltage output waveform of the grid-connected low-voltage feedback verification point are subjected to waveform fitting processing, and a preset curve fitting algorithm, including the least squares method, is used to perform waveform fitting processing, and the fitted waveform is used as the weak current test electrical characteristic waveform of the grid-connected low-voltage feedback verification point, and the weak current test electrical characteristic waveform of the centralized line feedback verification point is obtained by synchronous fitting through the least squares method;

[0113] According to the low-voltage side weak current test electrical characteristic reference calibration waveform in the continuous weak signal calibration data set, the weak current test electrical characteristic waveform of the grid-connected low-voltage feedback calibration point is compared and processed, and the total offset length and the maximum length of a single offset of the weak current test electrical characteristic waveform of the grid-connected low-voltage feedback calibration point are extracted and used as the continuous weak signal feedback element three;

[0114] According to the continuous weak signal feedback element three, the third indicator factor of the continuous weak signal injection test feedback verification is obtained. The specific execution constraints are:

[0115]

[0116] in, Feedback verification of the third indicator factor for continuous weak signal injection test, 、 They are the total offset length and the maximum length of a single offset of the weak current test electrical characteristic waveform of the grid-connected low-voltage feedback verification point, It is the defined offset length of the electrical characteristic waveform of the weak current test on the low voltage side of the grid. The third indicator impairment factor corresponding to the unit value of the maximum length of a single offset of the electrical characteristic waveform of the weak current test at the preset grid-connected low-voltage feedback verification point is is the preset third indication correction coefficient.

[0117] According to the weak current test electrical characteristic reference calibration waveform at the collection line in the continuous weak signal calibration data set, the weak current test electrical characteristic waveform at the collection line feedback calibration point is compared and processed, and the total offset length and the maximum length of a single offset of the weak current test electrical characteristic waveform at the collection line feedback calibration point are extracted and used as the continuous weak signal feedback element four;

[0118] According to the continuous weak signal feedback element four, the fourth indicator factor of the continuous weak signal injection test feedback verification is obtained. The specific execution constraints are:

[0119]

[0120] in, The fourth indicator factor is checked for continuous weak signal injection test feedback. 、 They are the total offset length and the maximum length of a single offset of the weak current test electrical characteristic waveform of the line feedback verification point. It is the defined offset length of the electrical characteristic waveform of the weak current test at the line collection point. The fourth indicator impairment factor corresponding to the unit value of the maximum length of a single offset of the electrical characteristic waveform of the weak current test at the preset line feedback verification point is is the preset fourth indication correction coefficient.

[0121] According to the weak current test electrical characteristic waveforms of the grid-connected low-voltage feedback check point and the centralized line feedback check point, the peak density and the trough density of the weak current test electrical characteristic waveforms of the grid-connected low-voltage feedback check point and the centralized line feedback check point are sequentially extracted and synchronously integrated as the continuous weak signal feedback element five;

[0122] In this embodiment, the peak density is the number of peaks existing in a unit length of the weak current test electrical characteristic waveform, and the trough density is the number of troughs existing in a unit length of the weak current test electrical characteristic waveform. The peak density and the trough density are both characteristic information of the weak current test electrical characteristic waveform of the grid-connected low-voltage feedback verification point and the centralized line feedback verification point. Analysis helps to understand the periodicity and frequency characteristics of the weak current test electrical characteristic waveform.

[0123] According to the continuous weak signal feedback element 5, the fifth indicator factor of the continuous weak signal injection test feedback verification is obtained. The specific execution constraints are:

[0124]

[0125] in, Feedback verification of the fifth indicator factor for continuous weak signal injection test, 、 They are the peak density of the weak current test electrical characteristic waveform of the grid-connected low-voltage feedback verification point and the centralized line feedback verification point, 、 They are the trough density of the weak current test electrical characteristic waveform of the grid-connected low-voltage feedback verification point and the centralized line feedback verification point, 、 They are the peak density definition deviation and the trough density definition deviation of the weak current test electrical characteristic waveform between the grid-connected low-voltage side and the line collection point, 、 They are the correction coefficients corresponding to the peak density and trough density of the electrical characteristic waveform of the weak current test.

[0126] The continuous weak signal feedback elements one, two, three, four and five are combined as the continuous weak signal injection test feedback parameters.

[0127] Furthermore, the test feedback performance evaluation index is obtained as follows:

[0128]

[0129] in, It represents the test feedback performance evaluation index of the new energy station. 、 They represent the short-term signal injection test feedback calibration index coefficient and the continuous weak signal injection test feedback calibration index coefficient of the new energy station respectively. 、 They represent the weighting factors for setting the short-time signal injection test feedback calibration index coefficient and the continuous weak signal injection test feedback calibration index coefficient, respectively. Indicates the initial reference evaluation index of the preset test feedback performance.

[0130] It should be noted that the test feedback performance evaluation indicators of new energy stations are specifically obtained by aggregating and integrating the short-time signal injection test feedback parameters, continuous weak signal injection test feedback parameters, short-time signal calibration data sets and continuous weak signal calibration data sets of the new energy stations, so as to comprehensively determine the test feedback performance of the new energy stations and serve as the numerical basis for the comprehensive performance evaluation warning feedback.

[0131] Preferably, the test feedback performance evaluation indicators of the new energy station can also use machine learning algorithms, such as support vector machines, random forests, neural networks, etc., to systematically train the data obtained from the test feedback to establish a model to evaluate the performance parameters of the new energy station and obtain the test feedback performance evaluation indicators of the new energy station.

[0132] Furthermore, the short-term signal injection test feedback calibration index coefficient of the new energy station and the continuous weak signal injection test feedback calibration index coefficient, among which the continuous weak signal injection test feedback calibration index coefficient of the new energy station , the specific execution constraints are:

[0133]

[0134] in, To provide feedback and check the indicator coefficient for continuous weak signal injection test of new energy stations. 、 、 、 、 The weight ratio coefficients corresponding to the first, second, third, fourth and fifth indicator factors of the preset continuous weak signal injection test feedback are checked in turn.

[0135] S400, performing a comprehensive performance evaluation warning feedback of the new energy station based on the test feedback performance evaluation index of the new energy station;

[0136] Specifically, the output of the new energy station connected to the grid during the supervision cycle is obtained, and the evaluation and warning model is introduced based on the performance evaluation indicators of the test feedback of the new energy station, which is expressed as:

[0137]

[0138] in, It represents the test feedback performance evaluation index of the new energy station. Indicates the final constraint indicator for reference of preset test feedback performance evaluation. Indicates the amount of power generated by new energy stations during the regulatory cycle. Indicates the reference constraint index for pre-loss reduction evaluation corresponding to the preset unit output on-grid capacity;

[0139] Obtain comprehensive performance evaluation warning feedback results of new energy stations and conduct evaluation warning feedback.

[0140] The present invention can perform short-term signal injection tests and continuous weak signal injection tests on new energy stations in a set regulatory cycle, and conduct comprehensive performance evaluation warning feedback on the new energy stations, breaking through the limitations caused by the current seldom targeted injection of disturbance signals with different characteristics to conduct specific performance evaluations on new energy stations. By performing short-term signal injection tests and continuous weak signal injection tests on new energy stations and conducting targeted data analysis, the dynamic response performance of new energy stations can be captured in a timely and effective manner, and the robustness of the performance evaluation of new energy stations is improved, so that a comprehensive performance optimization evaluation of new energy stations can be carried out, and potential performance problems and bottlenecks of new energy stations can be efficiently identified, thereby greatly improving the response and processing reliability of new energy stations in emergency situations.

[0141] By analyzing the constraint parameters of short-time signals and continuous weak signals, and extracting short-time signal calibration data sets and continuous weak signal calibration data sets, and by matching and screening the corresponding calibration data sets according to the characteristics of the test signals, the reliability, accuracy and test efficiency of the new energy station performance test can be improved, and the mutual adaptability and matching between the new energy station test and calibration data can be further increased, ensuring the full and effective utilization of the new energy station test data.

[0142] By comprehensively processing the short-term signal injection test feedback parameters and continuous weak signal injection test feedback parameters of the new energy station, the test feedback performance evaluation index of the new energy station is obtained, which can fully evaluate the operational reliability of the new energy station, and then ensure the operational safety of the new energy station, reduce the operational safety risks caused by performance failures, and help the new energy station to make reasonable adjustments and improvements, and improve the overall performance operation level.

[0143] The above is a schematic diagram of a method for online monitoring of new energy station performance based on active perturbation according to this embodiment. It should be noted that the technical solution of this system for online monitoring of new energy station performance based on active perturbation is based on the same concept as the technical solution of the method for online monitoring of new energy station performance based on active perturbation described above. For details not described in detail in the technical solution of the system for online monitoring of new energy station performance based on active perturbation according to this embodiment, please refer to the description of the technical solution of the method for online monitoring of new energy station performance based on active perturbation described above.

[0144] The online monitoring system for new energy station performance based on active disturbance in this embodiment, as shown in FIG2 , includes:

[0145] The performance active perturbation test module is used to perform active perturbation tests on new energy stations during a set regulatory cycle, including short-term signal injection tests and continuous weak signal injection tests, and analyze the constraint parameters of short-term signals and continuous weak signals in turn;

[0146] A performance verification data set extraction module is used to extract a short-term signal verification data set and a continuous weak signal verification data set according to the constraint parameters of the short-term signal and the continuous weak signal;

[0147] A station performance feedback parameter collection and processing module is used to collect feedback parameters of the short-term signal injection test and the continuous weak signal injection test of the new energy station, and obtain the test feedback performance evaluation index of the new energy station based on the short-term signal calibration data set and the continuous weak signal calibration data set;

[0148] A supervision feedback module, configured to provide a comprehensive performance evaluation warning feedback of the new energy station based on the test feedback performance evaluation indicators of the new energy station;

[0149] It also includes a supervision data warehouse for storing the verification data set corresponding to the short-time signal in each constraint parameter interval, and storing the verification data set corresponding to the continuous weak signal in each constraint parameter interval.

[0150] This embodiment further provides an electronic device suitable for online monitoring of new energy station performance based on active disturbance, including:

[0151] Memory and processor; the memory is used to store computer-executable instructions, and the processor is used to execute computer-executable instructions to implement the online supervision method of new energy station performance based on active disturbance as proposed in the above embodiment.

[0152] This embodiment also provides a storage medium having a computer program stored thereon, which, when executed by a processor, implements the method for online supervision of new energy station performance based on active disturbance as proposed in the above embodiment.

[0153] The storage medium proposed in this embodiment and the method for online supervision of new energy station performance based on active disturbance proposed in the above embodiment belong to the same inventive concept. Technical details not fully described in this embodiment can be referred to the above embodiment, and this embodiment has the same beneficial effects as the above embodiment.

[0154] Through the above description of the embodiments, those skilled in the art can clearly understand that the present invention can be implemented with the help of software and necessary general-purpose hardware. Of course, it can also be implemented with hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, can be embodied in the form of a software product. The computer software product can be stored in a computer-readable storage medium, such as a computer floppy disk, read-only memory (ROM), random access memory (RAM), flash memory (FLASH), hard disk or optical disk, etc., and includes a number of instructions for enabling a computer device (which can be a personal computer, server, or network device, etc.) to execute the methods of various embodiments of the present invention.

[0155] Example 2

[0156] Referring to Table 1, an embodiment of the present invention provides an online monitoring method for new energy station performance based on active disturbance. In order to verify its beneficial effects, the comparison results of two schemes are provided.

[0157] Table 1 is the experimental comparison data of the method of the present invention and the traditional method, and the data are as follows:

[0158] Table 1: Scheme comparison data table

[0159]

[0160] As can be seen from Table 1, the regulatory data matching rate of the present invention is 97%, indicating that the present invention can perform targeted data analysis and targeted matching and screening data, which can improve the reliability, accuracy and test efficiency of new energy station performance testing, and increase the mutual adaptability and matching between new energy station testing and calibration data; it is far superior to traditional methods in terms of response time and response accuracy, and improves the response processing reliability of new energy stations in emergency situations. It has a significant improvement in regulatory coverage and fault detection, and can conduct a comprehensive evaluation of the performance optimization of new energy stations, which can ensure the operational safety of new energy stations and reduce the operational safety risks caused by performance failures.

[0161] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to 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 online monitoring of new energy station performance based on active disturbance, characterized in that: include: Conduct active performance disturbance tests on new energy stations during the set regulatory cycle, including short-term signal injection tests and continuous weak signal injection tests, and analyze the constraint parameters of short-term signals and continuous weak signals in turn; Extracting a short-term signal verification data set and a continuous weak signal verification data set according to the constraint parameters of the short-term signal and the continuous weak signal; Collect feedback parameters of the short-term signal injection test and the continuous weak signal injection test of the new energy station, and obtain test feedback performance evaluation indicators of the new energy station based on the short-term signal calibration data set and the continuous weak signal calibration data set; Based on the test feedback performance evaluation indicators of the new energy station, a comprehensive performance evaluation warning feedback of the new energy station is carried out.

2. The method for online monitoring of new energy station performance based on active disturbance according to claim 1, characterized in that: The constraint parameters for analyzing short-term signals and continuous weak signals include: Conduct short-term signal injection tests on new energy stations during the set regulatory cycle and obtain the injected short-term signal data, including the short-term signal release intensity and short-term signal waveform; Extracting short-time signal waveform element information from the short-time signal waveform diagram, including short-time signal pulse width, short-time signal pulse duration, peak amplitude, peak point rise time, and peak point fall time; Performing numerical processing and analysis based on the short-time signal release intensity and short-time signal waveform element information to obtain constraint parameters of the short-time signal; Conduct continuous weak signal injection tests on new energy stations during the set regulatory cycle and obtain the injected continuous weak signal data, including the average release intensity of the continuous weak signal and the continuous weak signal waveform; Extracting continuous weak signal waveform element information according to the continuous weak signal waveform graph, including continuous weak signal average pulse width, single pulse average duration, pulse number and pulse frequency; According to the average release intensity of the continuous weak signal and the waveform element information of the continuous weak signal, the constraint parameters of the continuous weak signal are obtained through numerical analysis.

3. The method for online monitoring of new energy station performance based on active disturbance according to claim 1 or 2, characterized in that: Extracting short-term signal calibration data sets and continuous weak signal calibration data sets includes: According to the constraint parameters of the short-time signal, matching is performed with the calibration data sets corresponding to the short-time signal in each constraint parameter interval stored in the data warehouse to obtain the corresponding short-time signal calibration data set; According to the constraint parameters of the continuous weak signal, the continuous weak signal is matched with the calibration data set corresponding to each constraint parameter interval stored in the data warehouse to obtain the corresponding continuous weak signal calibration data set.

4. The method for online monitoring of new energy station performance based on active disturbance according to claim 3 is characterized in that: Collecting feedback parameters of the short-time signal injection test includes: In the short-time signal injection test, the feedback verification point pre-deployed on the high-voltage side of the grid connection point is marked as the grid connection high-voltage feedback verification point; Statistics are collected on the response parameters of the grid-connected high-voltage feedback verification point during the short-time signal injection test, which are marked as short-time signal injection test feedback parameters.

5. The method for online monitoring of new energy station performance based on active disturbance according to claim 4 is characterized in that: Collecting feedback parameters of the continuous weak signal injection test includes: In the continuous weak signal injection test, the feedback verification points deployed on the grid-connected low-voltage side and the central line are marked as grid-connected low-voltage feedback verification points and central line feedback verification points; Recording a period corresponding to the duration of the continuous weak signal injection test as a continuous weak signal test cycle, monitoring and extracting the current output waveform and the voltage output waveform of the grid-connected low-voltage feedback verification point and the centralized line feedback verification point during the continuous weak signal test cycle; Collect the time difference of the AGC and AVC adjustment response intervals set at the grid connection point as the first element of continuous weak signal feedback; Dividing the continuous weak signal test period into a plurality of weak signal test moments according to the current output waveform and the voltage output waveform of the grid-connected low-voltage feedback check point and the central line feedback check point, and calculating the current difference and voltage difference between the grid-connected low-voltage feedback check point and the central line feedback check point at the weak signal test moment as the second continuous weak signal feedback element; The current output waveform and the voltage output waveform of the grid-connected low-voltage feedback verification point are subjected to waveform fitting processing, and the waveform obtained by fitting is used as the weak current test electrical characteristic waveform of the grid-connected low-voltage feedback verification point, and the weak current test electrical characteristic waveform of the line-collecting feedback verification point is obtained by synchronous fitting; According to the low-voltage side weak current test electrical characteristic reference calibration waveform in the continuous weak signal calibration data set, the weak current test electrical characteristic waveform of the grid-connected low-voltage feedback calibration point is compared and processed, and the total offset length and the maximum length of a single offset of the weak current test electrical characteristic waveform of the grid-connected low-voltage feedback calibration point are extracted and used as the continuous weak signal feedback element three; According to the weak current test electrical characteristic reference calibration waveform at the collection line in the continuous weak signal calibration data set, the weak current test electrical characteristic waveform at the collection line feedback calibration point is compared and processed, and the total offset length and the maximum length of a single offset of the weak current test electrical characteristic waveform at the collection line feedback calibration point are extracted and used as the continuous weak signal feedback element four; According to the weak current test electrical characteristic waveforms of the grid-connected low-voltage feedback check point and the centralized line feedback check point, the peak density and the trough density of the weak current test electrical characteristic waveforms of the grid-connected low-voltage feedback check point and the centralized line feedback check point are sequentially extracted as the continuous weak signal feedback element five; The continuous weak signal feedback elements one, two, three, four and five are combined as the continuous weak signal injection test feedback parameters.

6. The method for online monitoring of new energy station performance based on active disturbance according to claim 5 is characterized in that: The test feedback performance evaluation index is expressed as: in, Represents the test feedback performance evaluation index of the new energy station, 、 They represent the short-term signal injection test feedback calibration index coefficient and the continuous weak signal injection test feedback calibration index coefficient of the new energy station respectively. 、 They represent the weighting factors for setting the short-time signal injection test feedback calibration index coefficient and the continuous weak signal injection test feedback calibration index coefficient, respectively. Indicates the initial reference evaluation index of the preset test feedback performance.

7. The method for online monitoring of new energy station performance based on active disturbance according to any one of claims 4 to 6, characterized in that: The comprehensive performance evaluation warning feedback includes: Obtain the grid-connected power output of the new energy stations during the supervision cycle, and import the evaluation and warning model based on the performance evaluation indicators of the test feedback of the new energy stations, which can be expressed as: in, Represents the test feedback performance evaluation index of the new energy station, Indicates the final constraint indicator for reference of preset test feedback performance evaluation. Indicates the amount of power generated by new energy stations during the regulatory cycle. Indicates the reference constraint index for pre-loss reduction evaluation corresponding to the preset unit output on-grid capacity; Obtain comprehensive performance evaluation warning feedback results of new energy stations and conduct evaluation warning feedback.

8. An online monitoring system for new energy station performance based on active disturbance, characterized in that: include, The performance active perturbation test module is used to perform active perturbation tests on new energy stations during a set regulatory cycle, including short-term signal injection tests and continuous weak signal injection tests, and analyze the constraint parameters of short-term signals and continuous weak signals in turn; A performance verification data set extraction module is used to extract a short-term signal verification data set and a continuous weak signal verification data set according to the constraint parameters of the short-term signal and the continuous weak signal; A station performance feedback parameter collection and processing module is used to collect feedback parameters of the short-term signal injection test and the continuous weak signal injection test of the new energy station, and obtain the test feedback performance evaluation index of the new energy station based on the short-term signal calibration data set and the continuous weak signal calibration data set; The supervision feedback module is used to provide a comprehensive performance evaluation warning feedback of the new energy station based on the test feedback performance evaluation indicators of the new energy station.

9. An electronic device comprising: memory and processor; The memory is used to store computer-executable instructions, and the processor is used to execute the computer-executable instructions. When the computer-executable instructions are executed by the processor, the steps of the online supervision method of new energy station performance based on active disturbance as described in any one of claims 1 to 7 are implemented.

10. A computer-readable storage medium storing computer-executable instructions, which, when executed by a processor, implement the steps of the method for online supervision of new energy station performance based on active disturbance as described in any one of claims 1 to 7.

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