A new energy station abnormal frequency processing method and system under wide frequency harmonic working conditions

Abstract

The application provides a new energy station abnormal frequency processing method and system under wide frequency harmonic working conditions, comprising: collecting instantaneous voltages of different electrical position measuring points of a new energy station; taking a power frequency as a period, calculating the number of zero-crossing points of the instantaneous voltages, and when the number of zero-crossing points of the voltages is abnormal, calculating the time interval between adjacent two zero-crossing points; and determining whether to lock the fast frequency modulation function of the new energy station based on the time interval between the adjacent two zero-crossing points and a set threshold. The application quickly determines whether to lock the fast frequency modulation function of the new energy station according to whether the number of zero-crossing points in the power frequency period is abnormal and the time interval between two zero-crossing points, effectively prevents the frequency modulation device from malfunctioning, reduces the frequency modulation action times of the new energy station, and improves the safety and stability of the power grid and the economy of the power generation units / energy storage devices in the station.

Description

Technical Field

[0001] This invention relates to the field of new energy access and control, specifically to a method and system for handling abnormal frequencies at new energy power stations under broadband harmonic operating conditions. Background Technology

[0002] For a considerable period in the future, a large number of wind farms and photovoltaic power plants (hereinafter referred to as new energy power plants) will be connected to the power grid, and new energy will gradually become the main power source. The power generation units of new energy power plants are connected to the grid through power electronic devices, and characteristics such as low inertia, weak support, and wideband harmonics will become more prominent. This requires new energy power plants to proactively take measures to overcome these adverse effects, such as actively participating in power system frequency regulation and wideband harmonic suppression. Wind farms should have rapid frequency regulation / response capabilities, and specific requirements are given for the inertia response and primary frequency regulation involved. For example, the active power rise time of the wind farm's inertia response is required to be no greater than 1 second, the active power rise time of primary frequency regulation no greater than 9 seconds, and the steady-state deviation no greater than ±1%. P n ( P n The rated power of new energy power stations places high demands on the real-time performance and accuracy of their rapid frequency regulation. Therefore, higher requirements are placed on the accuracy of frequency measurement results.

[0003] However, broadband harmonics present in frequency measurements can affect the accuracy of the results, potentially causing malfunctions in existing wind farm fast frequency regulation devices (including inertial response and primary frequency control). One effective method to prevent malfunctions is to add a bandpass filter (typically set to 0-100Hz) at the data processing front end. However, the presence of harmonics below 100Hz can lead to significant errors in frequency calculations. In such cases, if the fast frequency regulation mechanism of a renewable energy power station is triggered due to a large frequency calculation error, it will cause significant power fluctuations at the grid connection point, which is detrimental to grid security and stability and the economical operation of renewable energy power stations. It may even lead to the disconnection of some power generation units from the grid. Therefore, given the reality of high proportions of renewable energy and high proportions of power electronics, quickly identifying the main causes of grid frequency fluctuations and obtaining a more accurate grid frequency is crucial.

[0004] Current shortcomings: Under power system voltage waveform distortion conditions, especially when there are harmonics in the 0~100Hz frequency band (including subharmonics and ultra-low frequency harmonics), the frequency calculation error increases; the presence of broadband harmonics is prone to frequency over-limit events, leading to malfunctions of the fast frequency control strategy (primary frequency regulation and inertial response) of new energy power plants. Summary of the Invention

[0005] To address the issue that existing technologies using bandpass filters in broadband harmonic operating conditions can lead to significant errors in frequency calculations, resulting in substantial power fluctuations at the grid connection points of renewable energy power plants, this invention proposes a method for handling abnormal frequencies at renewable energy power plants under broadband harmonic operating conditions, comprising:

[0006] Collect instantaneous voltage at measurement points at different electrical locations in the new energy power station;

[0007] Using the power frequency as the period, calculate the number of instantaneous voltage zero-crossing points, and when the number of voltage zero-crossing points is abnormal, calculate the time interval between two adjacent zero-crossing points;

[0008] The locking and unlocking of the fast frequency regulation function of the new energy power station is determined based on the time interval between two adjacent zero crossings and the set threshold.

[0009] Preferably, the method of collecting the instantaneous voltage at different electrical locations of the new energy power station includes:

[0010] The system collects instantaneous voltage data from the grid connection point of the new energy power plant, instantaneous voltage data from the busbars within the power plant, and instantaneous voltage data from the output side of the power generation unit.

[0011] Preferably, determining the locking and unlocking of the fast frequency regulation function of the new energy power station based on the time interval between two adjacent zero crossings and a set minimum threshold and a set maximum threshold includes:

[0012] The decision on whether to temporarily disable the fast frequency regulation function of the new energy power station is based on the time interval of the instantaneous voltage at the grid connection point and the set minimum threshold.

[0013] When the fast frequency regulation function of the new energy power station is temporarily blocked, the time interval between the instantaneous voltage of the bus in the power station and / or the instantaneous voltage of the output side of the power generation unit and the set minimum threshold is used to determine whether to continue blocking the fast frequency regulation function of the new energy power station.

[0014] When the fast frequency regulation function of the new energy power station is continuously locked, the decision on whether to enable the fast frequency regulation function of the new energy power station is based on the time interval of the instantaneous voltage at the grid connection point and the set maximum threshold.

[0015] The set threshold includes a set minimum threshold and a set maximum threshold.

[0016] Preferably, the step of determining whether to temporarily disable the fast frequency regulation function of the renewable energy power station based on the time interval of the instantaneous voltage at the grid connection point and a set threshold includes:

[0017] When the time interval of the instantaneous voltage at the grid connection point is less than a preset threshold for at least two consecutive times, the fast frequency regulation function of the new energy power station is temporarily locked.

[0018] Preferably, when the fast frequency regulation function of the renewable energy power station is temporarily blocked, determining whether to continuously block the fast frequency regulation function of the renewable energy power station based on whether the time interval between the instantaneous voltage of the bus in the power station and / or the instantaneous voltage at the output side of the power generation unit is less than the set threshold includes:

[0019] When the time interval between the instantaneous voltage of the bus in the power station and / or the instantaneous voltage at the output side of the power generation unit is less than the set threshold, the fast frequency regulation function of the new energy power station is continuously blocked.

[0020] Preferably, when the fast frequency regulation function of the renewable energy power station is continuously locked, determining whether to enable the fast frequency regulation function of the renewable energy power station based on the time interval of the instantaneous voltage at the grid connection point and a set maximum threshold includes:

[0021] The fast frequency regulation function of the new energy power station is activated when the time interval of the instantaneous voltage at the grid connection point is greater than the set maximum threshold at least twice in a row.

[0022] Preferably, the step for determining the abnormal number of voltage zero-crossing points includes:

[0023] When the number of zero-crossing points of the instantaneous voltage at the grid connection point, the instantaneous voltage of the bus in the power station, and the instantaneous voltage at the output side of the power generation unit are greater than the number of zero-crossing points corresponding to the power frequency cycle, the number of voltage zero-crossing points is determined to be abnormal.

[0024] Preferably, the number of zero-crossing points corresponding to the power frequency cycle is calculated using the following formula:

[0025] S X = 2N+1

[0026] In the formula, N is the number of power frequency cycles.

[0027] Based on the same inventive concept, this invention also provides a system for handling abnormal frequencies in new energy power plants under broadband harmonic operating conditions, comprising:

[0028] The data acquisition module is used to collect the instantaneous voltage at different electrical locations in the new energy power station.

[0029] The calculation module is used to calculate the number of instantaneous voltage zero-crossing points with the power frequency as the period, and to calculate the time interval between two adjacent zero-crossing points when the number of voltage zero-crossing points is abnormal.

[0030] The control module is used to determine the locking and unlocking of the fast frequency regulation function of the new energy power station based on the time interval between two adjacent zero crossings and a set threshold.

[0031] Preferably, the control module includes:

[0032] The temporary blocking submodule is used to determine whether to temporarily block the fast frequency regulation function of the new energy power station based on the time interval of the instantaneous voltage at the grid connection point and a set threshold.

[0033] The continuous blocking submodule is used to determine whether to continuously block the fast frequency regulation function of the new energy power station when the fast frequency regulation function of the new energy power station is temporarily blocked, based on the time interval between the instantaneous voltage of the bus in the power station and / or the instantaneous voltage of the output side of the power generation unit and the set minimum threshold.

[0034] The enable submodule is used to determine whether to enable the fast frequency regulation function of the new energy power station based on the time interval of the instantaneous voltage at the grid connection point and the set maximum threshold when the fast frequency regulation function of the new energy power station is continuously locked.

[0035] The set threshold includes a set minimum threshold and a set maximum threshold.

[0036] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0037] This invention provides a method for handling abnormal frequencies at renewable energy power plants under broadband harmonic operating conditions. The method includes: collecting instantaneous voltage data from measurement points at different electrical locations within the renewable energy power plant; calculating the number of zero-crossing points of the instantaneous voltage using the power frequency as a period; and calculating the time interval between two adjacent zero-crossing points when the number of zero-crossing points is abnormal; and determining whether to lock or unlock the rapid frequency regulation function of the renewable energy power plant based on the time interval between two adjacent zero-crossing points and a set threshold. This invention quickly determines whether to lock the rapid frequency regulation function of the renewable energy power plant by checking whether the number of zero-crossing points within the power frequency period is abnormal and by considering the time interval between two zero-crossing points. This effectively prevents malfunctions in frequency regulation, reduces the number of frequency regulation actions at renewable energy power plants, and improves the safety and stability of the power grid and the economic efficiency of wind turbines / energy storage devices within the power plant. Attached Figure Description

[0038] Figure 1 This is a flowchart of a method for handling abnormal frequencies in new energy power stations under broadband harmonic operating conditions according to the present invention.

[0039] Figure 2 This is a schematic diagram of the measurement points at different electrical locations in the new energy power station according to the present invention;

[0040] Figure 3 This is a flowchart of the abnormal frequency identification method for new energy power stations under broadband harmonic operating conditions according to the present invention. Detailed Implementation

[0041] This invention proposes a method and system for handling abnormal frequencies at renewable energy power plants under broadband harmonic conditions. When abnormal frequency changes occur at a renewable energy power plant due to broadband harmonics, the system quickly identifies these changes and determines whether to lock out the rapid frequency response control and whether to implement broadband harmonic suppression measures. It avoids voltage filtering and identifies the actual grid frequency change trend, facilitating accurate judgment of whether to implement or lock out the rapid frequency control strategy at the renewable energy power plant. Based on the processed voltage data from the grid connection point and different electrical locations within the power plant, it simultaneously identifies the dominant factors causing frequency exceedances and locks out or maintains the rapid frequency control as needed, implementing broadband harmonic suppression strategies when necessary. This reduces misjudgments and ensures the economical operation of renewable energy power plants and the safe and stable operation of the power system. It requires no additional hardware, can run in parallel with existing frequency calculation and processing methods, and has good portability.

[0042] Compared with existing technologies, this method does not actively filter the collected voltage, shortens the calculation and processing time, and has no phase angle offset. This is conducive to the rapid intervention of frequency control strategies or the prevention of malfunctions, ensuring the safe, stable and economical operation of the power system / new energy power plant.

[0043] Example 1:

[0044] A method for handling abnormal frequencies in new energy power plants under broadband harmonic operating conditions, such as Figure 1 As shown:

[0045] S1: Collect the instantaneous voltage at measurement points in different electrical locations of the new energy power station;

[0046] S2: Using the power frequency as the period, calculate the number of instantaneous voltage zero-crossing points, and when the number of voltage zero-crossing points is abnormal, calculate the time interval between two adjacent zero-crossing points;

[0047] S3: Determine the locking and unlocking of the fast frequency regulation function of the new energy power station based on the time interval between the two adjacent zero crossings and the set threshold.

[0048] This invention provides a method for handling abnormal frequencies in new energy power plants under broadband harmonic operating conditions, including:

[0049] The instantaneous voltage at different electrical location measurement points in S1 is collected, specifically including:

[0050] Measurement points at different electrical locations in new energy power stations, such as Figure 2 As shown, it includes the grid connection point of the new energy power station, the 35kV / 10kV busbar, and the output side of the power generation unit (wind turbine / photovoltaic inverter).

[0051] The instantaneous voltage U of the new energy power station was collected using a fixed sampling rate. H Instantaneous voltage U of the busbar within the stationM The instantaneous voltage UL at the output side of the power generation unit (wind turbine / photovoltaic inverter) is 35kV / 10kV bus instantaneous voltage in the station.

[0052] S2 calculates the number of instantaneous voltage zero-crossings using the power frequency as the period, and calculates the time interval between two adjacent zero-crossings when the number of voltage zero-crossings is abnormal. Specifically, this includes:

[0053] Calculate the instantaneous voltage U using the power frequency as the period. H U M and U L The number of zero crossings is used to initially determine if there are any anomalies;

[0054] If the number of zero-crossing points is abnormal, then calculate U. H U M and U L The time interval T between two adjacent zero crossings H T M and T L .

[0055] S3, which determines the locking and unlocking of the fast frequency regulation function of the new energy power station based on the time interval between two adjacent zero crossings and a set threshold, specifically includes:

[0056] Determine T H Is it less than the set threshold T? x (e.g., T) x (Set to 0.5ms), if T occurs at least twice consecutively H If the value is less than the set minimum threshold, the fast frequency regulation function of the new energy power station will be temporarily locked for 0.2 seconds, which effectively prevents frequency regulation malfunctions and reduces the number of times the new energy power station participates in frequency regulation.

[0057] Simultaneously combined with T M and T L The calculation results are used to determine whether to continuously block the fast frequency regulation function of the new energy power station. If T M and T L The case where any one of them has the same condition (i.e., T) M or T L Less than T x If the function is blocked, then consider implementing a broadband harmonic suppression strategy.

[0058] Determine the instantaneous voltage U at the grid connection point H The time interval T between two adjacent zero crossings H Does it exceed the set maximum threshold T twice consecutively? y (e.g., T) y (Set to 9.5ms), if it exceeds the set maximum threshold T yThen the fast frequency regulation function of the new energy power station will be restored;

[0059] Repeat the above steps.

[0060] like Figure 3 The flowchart shown is a method for identifying abnormal frequencies in new energy power plants under broadband harmonic operating conditions. The specific execution steps are as follows:

[0061] Step 1: Collect the instantaneous voltage at the grid connection point of the new energy power station, the instantaneous voltage of the 35kV / 10kV bus within the station, and the instantaneous voltage at the output of the power generation unit using a fixed sampling rate, and record them as U. H U M and U L ;

[0062] Step 2: Using the power frequency as the period and the next zero-crossing point as the starting point, calculate the instantaneous voltage value U for the previous N power frequency cycles. H U M and U L The number S of zero-crossing points (all three phase voltages A, B, and C need to be monitored) H- S M- S L- If S H- =S M- =S L- =S X If S H- >S X Then proceed to step 3; use formula (1) to calculate S. X If set to 10 power frequency cycles, then S X =21;

[0063] S X = 2N+1 (1)

[0064] Where N is the number of power frequency cycles, S X The number of zero-crossings within N power frequency cycles.

[0065] Step 3: Using the power frequency as the period and the next zero-crossing point as the starting point, calculate the instantaneous voltage value U for the next power frequency cycle. H U M and U L The number S of zero-crossing points (all three phase voltages A, B, and C need to be monitored) H+ S M+ and S L+ If S H+ =S M+ =S L+ And S H+ =S X If S H+ >S XThen proceed to step 4;

[0066] Step 4: Calculate the time interval T between the zero-crossing points of the voltage at different electrical positions of the new energy power station according to formula (2). H+ T M+ and T L+ Calculate according to formula (2);

[0067] T H+ = T H1+ -T H2+ (2)

[0068] Among them, T H1+ and T H2+ These are the time coordinates of two adjacent zero-crossing points.

[0069] Step 5: Determine T H+ Is it less than the set minimum threshold T? x If T H+ <T X If so, the rapid frequency regulation function of the new energy power station will be temporarily disabled;

[0070] Step 6: Calculate T M and T L If T exists M <T X or T L <T X If so, the fast frequency regulation function of the new energy power station will be continuously blocked, and a broadband harmonic suppression strategy will be considered.

[0071] Step 7: Calculate the next power frequency cycle, T H Is it greater than the set maximum threshold T? y If T H >T y Then the rapid frequency regulation function of the new energy power station will be restarted;

[0072] Step 8: Repeat steps 1 through 7.

[0073] This invention achieves the following effects:

[0074] (1) Quickly determine whether the main cause of frequency anomalies in new energy power plants is power imbalance in the power system or broadband harmonics, and determine whether to block / engage control strategies such as fast frequency regulation control and broadband harmonic suppression.

[0075] (2) Without filtering the instantaneous voltage values ​​collected, the frequency calculation results are closer to the actual values. When there are wideband harmonics (especially harmonics in the 0-100Hz band) in the system, the accuracy of the frequency calculation is better than the result after filtering, providing reliable support for the rapid frequency regulation (inertia response and primary frequency regulation) of wind farms;

[0076] (3) When broadband harmonics are determined to be the dominant factor, the fast frequency regulation control strategy of the new energy power station should be temporarily locked to avoid malfunctions. This effectively reduces the number of times the new energy power station participates in frequency regulation, improving the economic efficiency of wind turbines and energy storage devices;

[0077] (4) It does not require additional system hardware; it is achieved by optimizing the control strategy in the software, making it easy to implement on-site.

[0078] (5) It has good scalability, can run in parallel with existing frequency modulation control strategies, and has good portability.

[0079] Example 2:

[0080] The following is an illustration using a specific case.

[0081] It operates in parallel with the existing fast frequency control strategy for new energy power plants, using a fixed sampling rate. In this embodiment, 20kHz is used to collect the instantaneous voltage U at the grid connection point of the new energy power plant. H Instantaneous voltage U of the 35kV busbar within the substation M Instantaneous voltage U at the output side of the power generation unit (wind turbine / photovoltaic inverter) L And the instantaneous voltage U at the grid connection point was collected. H Instantaneous voltage U of the 35kV busbar within the substation M Instantaneous voltage U at the output side of the power generation unit (wind turbine / photovoltaic inverter) L Stored in the wind farm's fast frequency regulation controller for backup;

[0082] Using the power frequency cycle as the period, in this embodiment, the power frequency cycle is 0.2s, to calculate the instantaneous voltage U. H U M and U L The number of zero-crossing points is counted, and an initial judgment is made as to whether there is any abnormality; if the number of zero-crossing points is abnormal, proceed to the next step, otherwise return to the previous step;

[0083] In the next power frequency cycle, calculate U respectively. H U M and U L The time interval T between two adjacent zero crossings H T M and T L ;

[0084] Determine T H Is it less than the set minimum threshold T? x In this embodiment, T x Set to 0.5ms, if T H If the value is less than the set minimum threshold, the fast frequency regulation function of the new energy power station will be temporarily locked for 0.02 seconds.

[0085] Combined with T M and T L The calculation results determine whether to continuously lock out the fast frequency regulation function of the new energy power station. If T M and T L If any one of them has a time interval exceeding the set minimum threshold T x If so, the function will remain locked and a trigger signal for the wideband harmonic suppression strategy will be given.

[0086] Determine U H Does the calculation result exceed the set maximum threshold T twice consecutively? y (e.g., T) y (Set to 9.5ms); if it exceeds the set maximum threshold T y Then the fast frequency regulation function of the new energy power station will be restored;

[0087] Repeat the steps above.

[0088] Example 3

[0089] Based on the same inventive concept, this invention also provides a system for handling abnormal frequencies in new energy power plants under broadband harmonic operating conditions, comprising:

[0090] The data acquisition module is used to collect the instantaneous voltage at different electrical locations in the new energy power station.

[0091] The calculation module is used to calculate the number of instantaneous voltage zero-crossing points with the power frequency as the period, and to calculate the time interval between two adjacent zero-crossing points when the number of voltage zero-crossing points is abnormal.

[0092] The control module is used to determine the locking and unlocking of the fast frequency regulation function of the new energy power station based on the time interval between two adjacent zero crossings and a set threshold.

[0093] The control module includes:

[0094] The temporary blocking submodule is used to determine whether to temporarily block the fast frequency regulation function of the new energy power station based on the time interval of the instantaneous voltage at the grid connection point and a set threshold.

[0095] The continuous blocking submodule is used to determine whether to continuously block the fast frequency regulation function of the new energy power station when the fast frequency regulation function of the new energy power station is temporarily blocked, based on the time interval between the instantaneous voltage of the bus in the power station and / or the instantaneous voltage of the output side of the power generation unit and the set minimum threshold.

[0096] The enable submodule is used to determine whether to enable the fast frequency regulation function of the new energy power station based on the time interval of the instantaneous voltage at the grid connection point and the set maximum threshold when the fast frequency regulation function of the new energy power station is continuously locked.

[0097] The set threshold includes setting a minimum threshold and setting a maximum threshold.

[0098] For ease of description, the various parts of the above device are described separately as modules or units based on their functions. Of course, in implementing this application, the functions of each module or unit can be implemented in one or more software or hardware components.

[0099] Based on the same inventive concept, in another embodiment of the present invention, a computing device is provided. This computing device includes a processor and a memory. The memory stores a computer program, which includes program instructions. The processor executes the program instructions stored in the computer storage medium. The processor may be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. It is the computing and control core of the terminal, suitable for implementing one or more instructions, specifically suitable for loading and executing one or more instructions in the computer storage medium to achieve a corresponding method flow or corresponding function. The processor described in this embodiment of the present invention can be used to execute the steps of a method for handling abnormal frequencies in new energy power stations under broadband harmonic operating conditions.

[0100] Based on the same inventive concept, in another embodiment of the present invention, a storage medium is provided, specifically a computer-readable storage medium (Memory). This computer-readable storage medium is a memory device in a computer device used to store programs and data. It is understood that the computer-readable storage medium here can include both the built-in storage medium in the computer device and extended storage media supported by the computer device. The computer-readable storage medium provides storage space that stores the terminal's operating system. Furthermore, this storage space also stores one or more instructions suitable for loading and execution by a processor. These instructions can be one or more computer programs (including program code). It should be noted that the computer-readable storage medium here can be a high-speed RAM memory or a non-volatile memory, such as at least one disk storage device. The processor can load and execute one or more instructions stored in the computer-readable storage medium to implement the corresponding steps of the abnormal frequency processing method for new energy power stations under broadband harmonic operating conditions in the above embodiment.

[0101] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0102] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0103] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0104] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0105] The above are merely embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention are included within the scope of the claims of the present invention pending approval.

Claims

1. A method for handling abnormal frequencies in new energy power plants under broadband harmonic operating conditions, characterized in that, include: Collect instantaneous voltage at measurement points at different electrical locations in the new energy power station; Using the power frequency as the period, calculate the number of instantaneous voltage zero-crossing points, and when the number of voltage zero-crossing points is abnormal, calculate the time interval between two adjacent zero-crossing points; The locking and unlocking of the fast frequency regulation function of the new energy power station are determined based on the time interval between two adjacent zero crossings and the set threshold. The instantaneous voltage at different electrical locations of the new energy power station is collected, including: Collect instantaneous voltage at the grid connection point of the new energy power station, instantaneous voltage of the bus within the power station, and instantaneous voltage at the output side of the power generation unit; The method of determining the locking and unlocking of the fast frequency regulation function of the new energy power station based on the time interval between two adjacent zero crossings and a set threshold includes: The decision on whether to temporarily disable the fast frequency regulation function of the new energy power station is based on the time interval of the instantaneous voltage at the grid connection point and the set minimum threshold. When the fast frequency regulation function of the new energy power station is temporarily blocked, the time interval between the instantaneous voltage of the bus in the power station and / or the instantaneous voltage of the output side of the power generation unit and the set minimum threshold is used to determine whether to continue blocking the fast frequency regulation function of the new energy power station. When the fast frequency regulation function of the new energy power station is continuously locked, the decision on whether to enable the fast frequency regulation function of the new energy power station is based on the time interval of the instantaneous voltage at the grid connection point and the set maximum threshold. The set threshold includes a set minimum threshold and a set maximum threshold; The method of determining whether to temporarily disable the fast frequency regulation function of new energy power plants based on the time interval of the instantaneous voltage at the grid connection point and a set minimum threshold includes: When the time interval of the instantaneous voltage at the grid connection point is less than the set minimum threshold for at least two consecutive times, the fast frequency regulation function of the new energy power station is temporarily locked. When the fast frequency regulation function of the renewable energy power station is temporarily blocked, the determination of whether to continuously block the fast frequency regulation function of the renewable energy power station is based on the time interval between the instantaneous voltage of the bus and / or the instantaneous voltage of the generator unit outlet side within the power station and the set minimum threshold, including: When the time interval between the instantaneous voltage of the busbar and / or the instantaneous voltage at the output side of the power generation unit in the power station is less than the set minimum threshold, the fast frequency regulation function of the new energy power station is continuously locked. When the fast frequency regulation function of the renewable energy power station is continuously locked, determining whether to enable the fast frequency regulation function of the renewable energy power station based on the time interval of the instantaneous voltage at the grid connection point and the set maximum threshold includes: The fast frequency regulation function of the new energy power station is activated when the time interval of the instantaneous voltage at the grid connection point is greater than the set maximum threshold at least twice in a row.

2. The method as described in claim 1, characterized in that, The steps for determining the abnormal number of voltage zero-crossing points include: When the number of zero-crossing points of the instantaneous voltage at the grid connection point, the instantaneous voltage of the bus in the power station, and the instantaneous voltage at the output side of the power generation unit are greater than the number of zero-crossing points corresponding to the power frequency cycle, the number of voltage zero-crossing points is determined to be abnormal.

3. The method as described in claim 2, characterized in that, The number of zero-crossing points corresponding to the power frequency cycle is calculated using the following formula: S X = 2N+1 In the formula, N is the number of power frequency cycles, and S X This represents the number of zero-crossing points corresponding to the power frequency cycle.

4. A system for implementing the method for handling abnormal frequencies at new energy power stations under broadband harmonic operating conditions as described in any one of claims 1-3, characterized in that, include: The data acquisition module is used to collect the instantaneous voltage at different electrical locations in the new energy power station. The calculation module is used to calculate the number of instantaneous voltage zero-crossing points with the power frequency as the period, and to calculate the time interval between two adjacent zero-crossing points when the number of voltage zero-crossing points is abnormal. The control module is used to determine the locking and unlocking of the fast frequency regulation function of the new energy power station based on the time interval between two adjacent zero crossings and a set threshold.

5. The system as described in claim 4, characterized in that, The control module includes: The temporary blocking submodule is used to determine whether to temporarily block the fast frequency regulation function of the new energy power station based on the time interval of the instantaneous voltage at the grid connection point and the set threshold. The continuous blocking submodule is used to determine whether to continuously block the fast frequency regulation function of the new energy power station when the fast frequency regulation function of the new energy power station is temporarily blocked, based on the time interval between the instantaneous voltage of the bus in the station and / or the instantaneous voltage of the output side of the power generation unit and the set minimum threshold. The enable submodule is used to determine whether to enable the fast frequency regulation function of the new energy power station based on the time interval of the instantaneous voltage at the grid connection point and the set maximum threshold when the fast frequency regulation function of the new energy power station is continuously locked. The set threshold includes a set minimum threshold and a set maximum threshold.

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