Power grid broadband oscillation monitoring and alarming method, system and equipment and storage medium

Abstract

The invention belongs to the field of electric power automation, and discloses a power grid broadband oscillation monitoring and alarming method, system and device and a storage medium, and the method comprises the steps: obtaining the oscillation monitoring type and oscillation monitoring data of an oscillation monitoring point; and based on the oscillation monitoring data, obtaining an oscillation monitoring alarm result through an oscillation monitoring judgment method corresponding to the oscillation monitoring type. Different oscillation monitoring and judging methods are adopted for different oscillation monitoring types, an oscillation monitoring and judging method combining a time domain analysis method, an FFT algorithm and a Prony algorithm is adopted for ultralow-frequency oscillation or low-frequency oscillation, and an oscillation monitoring and judging method combining the time domain analysis method and the FFT algorithm is adopted for subsynchronous oscillation. For sub / super-synchronous oscillation or medium-high frequency oscillation, an oscillation monitoring and judging method based on combination of a main station and a substation is adopted, the problem of error analysis caused by frequency aliasing in data window selection and data analysis resampling of a pure Prony algorithm is effectively solved, and the warning efficiency is improved by improving the calculation effectiveness of the Prony algorithm.

Description

Technical Field

[0001] The invention belongs to the field of electric power automation and relates to a method, system, equipment and storage medium for monitoring and warning of broadband oscillation of a power grid. Background Art

[0002] With the rapid development of new energy and the construction of UHV AC and DC transmission projects, power electronic equipment is widely used in power grids. The current power grid presents the dual characteristics of high proportion of new energy and high proportion of power electronic equipment. Unlike traditional synchronous generators, power electronic equipment realizes energy conversion and grid connection through fast switching of switches and multi-time scale control. Moreover, because different types of power electronic equipment have different control modes, their interaction with the power grid injects a large amount of non-industrial frequency electrical quantities into the power grid, which may cause new broadband oscillations from sub / super synchronous to medium and high frequency bands, which has caused many oscillation accidents.

[0003] For the monitoring of broadband oscillations, the existing broadband measurement devices are compatible with the WAMS (Wide Area Measurement System) functional system and channels, realizing unified real-time measurement of the fundamental wave, interharmonics, harmonics and oscillation power components of the power grid within the range of 2500Hz, and transmitting the data to the master station in a time-division multiplexing manner. The master station WAMS receives the data and carries out broadband oscillation monitoring and alarm. Among them, broadband oscillations are mainly divided into ultra-low frequency (0.02-0.1Hz), low-frequency oscillation (0.1-2.5Hz), sub- / super-synchronous oscillation (2.5-100Hz) and medium- and high-frequency oscillation (100-2500Hz) according to different frequency bands. However, due to differences in specific implementation among various manufacturers, the effects of oscillation monitoring are inconsistent.

[0004] At present, broadband oscillation monitoring is mostly based on power grid components, which are divided into several types such as transformers, lines and generators. When the oscillation amplitude exceeds the set amplitude and meets the duration requirement, an alarm is issued. The alarm applied by the master station currently uses a fixed threshold or simply sets different thresholds according to the voltage level. At present, the algorithm is mainly based on the Prony algorithm, which is a method of fitting equally spaced sampling data with a linear combination of exponential terms. However, in actual application, problems such as insufficient performance, calculation timeout and data anomalies often occur. Although the Prony algorithm uses an exponential power signal model that is more suitable for oscillation monitoring, the original signal needs to be downsampled during the calculation of the Prony algorithm, which makes it impossible to avoid frequency aliasing and is time-consuming. Summary of the invention

[0005] The purpose of the present invention is to overcome the above-mentioned shortcomings of the prior art and provide a method, system, device and storage medium for monitoring and warning of broadband oscillation in a power grid.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] In a first aspect, the present invention provides a method for monitoring and alarming broadband oscillations of a power grid, comprising: obtaining an oscillation monitoring type and oscillation monitoring data of an oscillation monitoring point; based on the oscillation monitoring data, obtaining an oscillation monitoring alarm result by an oscillation monitoring judgment method corresponding to the oscillation monitoring type; wherein, when the oscillation monitoring type is ultra-low frequency oscillation or low frequency oscillation, the oscillation monitoring judgment method is: judging whether the fluctuation of the oscillation monitoring data exceeds the set dead zone based on a time domain analysis method; and when the fluctuation of the oscillation monitoring data exceeds the set dead zone, judging whether the oscillation monitoring data belongs to the frequency band of the current monitored oscillation type based on an FFT algorithm; and when the oscillation monitoring data belongs to the frequency band of the current monitored oscillation type, performing an oscillation alarm judgment based on a Prony algorithm to obtain an oscillation monitoring alarm result; when the oscillation monitoring type is subsynchronous oscillation, the oscillation monitoring judgment method is: judging whether the fluctuation of the oscillation monitoring data exceeds the set dead zone based on a time domain analysis method; and when the fluctuation of the oscillation monitoring data exceeds the set dead zone, performing an oscillation alarm judgment based on an FFT ... / supersynchronous oscillation or medium and high frequency oscillation, the oscillation monitoring judgment method is: an oscillation monitoring judgment method based on a combination of a master and a substation.

[0008] Optionally, when obtaining the oscillation monitoring type and oscillation monitoring data, when the oscillation monitoring type is ultra-low frequency oscillation, low frequency oscillation or subsynchronous oscillation, the oscillation monitoring data is active power data; when the oscillation monitoring type is sub / supersynchronous oscillation or medium and high frequency oscillation, the oscillation monitoring data is the instantaneous oscillation power component or interharmonic current data sent by the substation; wherein, all oscillation monitoring points perform oscillation monitoring and alarm of ultra-low frequency oscillation, low frequency oscillation and subsynchronous oscillation, and wide-band oscillation monitoring points perform oscillation monitoring and alarm of sub / supersynchronous oscillation and medium and high frequency oscillation.

[0009] Optionally, the time domain analysis method-based method for determining whether the fluctuation of the oscillation monitoring data exceeds the set dead zone includes: obtaining the current time window data according to the oscillation monitoring type and the oscillation monitoring data, and obtaining the difference between the maximum value of the oscillation monitoring data and the minimum value of the oscillation monitoring data in the current time window data; when the difference between the maximum value of the oscillation monitoring data and the minimum value of the oscillation monitoring data exceeds the set dead zone, the fluctuation of the oscillation monitoring data exceeds the set dead zone; when the difference between the maximum value of the oscillation monitoring data and the minimum value of the oscillation monitoring data does not exceed the set dead zone, the fluctuation of the oscillation monitoring data does not exceed the set dead zone, and returning to perform oscillation monitoring judgment for the next time window data.

[0010] Optionally, the FFT algorithm-based judgment of whether the oscillation monitoring data belongs to the frequency band of the currently monitored oscillation type includes: obtaining the earlier of the moment of maximum value and the moment of minimum value of the oscillation monitoring data in the current time window data to obtain the starting time; obtaining the data after the starting time in the current time window data to obtain the data to be analyzed; and performing spectral analysis on the data to be analyzed using the FFT algorithm to obtain the frequency corresponding to the maximum amplitude of the data to be analyzed, and judging whether the frequency corresponding to the maximum amplitude belongs to the frequency band of the currently monitored oscillation type; when the frequency corresponding to the maximum amplitude belongs to the frequency band of the currently monitored oscillation type, the oscillation monitoring data belongs to the frequency band of the currently monitored oscillation type; when the frequency corresponding to the maximum amplitude does not belong to the frequency band of the currently monitored oscillation type, the oscillation monitoring data does not belong to the frequency band of the currently monitored oscillation type, and returns to perform oscillation monitoring judgment for the next time window data.

[0011] Optionally, the oscillation alarm judgment based on the Prony algorithm to obtain the oscillation monitoring alarm result includes: analyzing the current time window data based on the Prony algorithm to obtain the dominant component amplitude and the dominant component frequency of the current time window data, and when the dominant component amplitude is greater than the difference between the maximum value of the oscillation monitoring data and the minimum value of the oscillation monitoring data, updating the dominant component amplitude to the difference between the maximum value of the oscillation monitoring data and the minimum value of the oscillation monitoring data; continuously obtaining the dominant component amplitude of a preset number of time window data and taking the average value to obtain the oscillation monitoring value; wherein, when continuously obtaining the dominant component amplitude of a preset number of time window data, when the current dominant component amplitude is less than half of the oscillation amplitude threshold preset at the oscillation monitoring point, returning to perform the oscillation monitoring judgment for the next time window data; the preset number W num Obtained by the following formula:

[0012]

[0013] Where N is the continuous frequency obtained by the preset oscillation time threshold of the oscillation monitoring point, f osc is the dominant component frequency of the current time window data, T slid The time window length of the time window data.

[0014] When the oscillation monitoring value is greater than the preset oscillation amplitude threshold of the oscillation monitoring point, the oscillation monitoring alarm result is an oscillation alarm, and the start time of the oscillation is the current time minus

[0015] The oscillation alarm judgment based on the FFT algorithm to obtain the oscillation monitoring alarm result includes: analyzing the current time window data based on the FFT algorithm to obtain the dominant component amplitude and the dominant component frequency of the current time window data, and when the dominant component amplitude is greater than the difference between the maximum value of the oscillation monitoring data and the minimum value of the oscillation monitoring data, updating the dominant component amplitude to the difference between the maximum value of the oscillation monitoring data and the minimum value of the oscillation monitoring data; continuously obtaining the dominant component amplitude of a preset number of time window data and taking the average value to obtain the oscillation monitoring value; wherein, when continuously obtaining the dominant component amplitude of a preset number of time window data, when the current dominant component amplitude is less than half of the preset oscillation amplitude threshold of the oscillation monitoring point, returning to perform the oscillation monitoring judgment of the next time window data; the preset number W num Obtained by the following formula:

[0016]

[0017] Where N is the continuous frequency obtained by the preset oscillation time threshold of the oscillation monitoring point, f osc is the dominant component frequency of the current time window data, T slid The time window length of the time window data.

[0018] When the oscillation monitoring value is greater than the preset oscillation amplitude threshold of the oscillation monitoring point, the oscillation monitoring alarm result is an oscillation alarm, and the start time of the oscillation is the current time minus Among them, the oscillation time threshold and oscillation amplitude threshold preset at the oscillation monitoring point are set according to the voltage level and oscillation monitoring type.

[0019] Optionally, when the difference between the maximum value and the minimum value of the oscillation monitoring data exceeds the set dead zone, the first mark value of the oscillation monitoring point is 1; when the difference between the maximum value and the minimum value of the oscillation monitoring data does not exceed the set dead zone, the first mark value of the oscillation monitoring point is 0; when the frequency corresponding to the maximum amplitude belongs to the frequency band of the current monitored oscillation type, the second mark value of the oscillation monitoring point is 1; when the frequency corresponding to the maximum amplitude does not belong to the frequency band of the current monitored oscillation type, the second mark value of the oscillation monitoring point is 0; when the dominant component amplitude is greater than the difference between the maximum value and the minimum value of the oscillation monitoring data, the third mark value of the oscillation monitoring point is 1; when the first mark value of the oscillation monitoring point is 1 and the third mark value is 1, when the oscillation monitoring judgment of the time window data is performed, when the fluctuation of the oscillation monitoring data exceeds the set dead zone, the oscillation alarm judgment is directly performed based on the Prony algorithm to obtain the oscillation monitoring alarm result; wherein, when the dominant component amplitude of a preset number of time window data is continuously obtained, when the current dominant component amplitude is less than half of the preset oscillation amplitude threshold of the oscillation monitoring point, the first mark value, the first mark value and the third mark value of the oscillation monitoring point are all 0.

[0020] Optionally, when the current time window data is obtained according to the oscillation monitoring type and the oscillation monitoring data: when the oscillation monitoring type is an ultra-low frequency oscillation of 0.02 to 0.1 Hz, the time window length of the time window data is set to 100s, and the time window overlap length is 50s; when the oscillation monitoring type is a low frequency oscillation of 0.1 to 0.5 Hz, the time window length of the time window data is set to 20s, and the time window overlap length is 10s; when the oscillation monitoring type is a low frequency oscillation of 0.5 to 2.5 Hz, the time window length of the time window data is set to 10s, and the time window overlap length is 5s; when the oscillation monitoring type is a subsynchronous oscillation of 2.5 to 25 Hz, the time window length of the time window data is set to 10s, and the time window overlap length is 2s; when the oscillation monitoring type is sub / supersynchronous oscillation or medium and high frequency oscillation, the time window length of the time window data is set to 2s, and the time window overlap length is 0s.

[0021] In a second aspect, the present invention provides a power grid broadband oscillation monitoring and alarm system, including: a data acquisition module, used to obtain the oscillation monitoring type and oscillation monitoring data of the oscillation monitoring point; an oscillation monitoring module, used to obtain the oscillation monitoring alarm result based on the oscillation monitoring data by an oscillation monitoring judgment method corresponding to the oscillation monitoring type; wherein, when the oscillation monitoring type is an ultra-low frequency oscillation or a low frequency oscillation, the oscillation monitoring judgment method is: based on a time domain analysis method, judging whether the fluctuation of the oscillation monitoring data exceeds a set dead zone; and when the fluctuation of the oscillation monitoring data exceeds the set dead zone, judging whether the oscillation monitoring data belongs to the current monitoring oscillation based on an FFT algorithm. The oscillation monitoring type is within the frequency band of the current monitored oscillation type; and when the oscillation monitoring data belongs to the frequency band of the currently monitored oscillation type, an oscillation alarm judgment is performed based on the Prony algorithm to obtain an oscillation monitoring alarm result; when the oscillation monitoring type is subsynchronous oscillation, the oscillation monitoring judgment method is: based on the time domain analysis method to judge whether the fluctuation of the oscillation monitoring data exceeds the set dead zone; and when the fluctuation of the oscillation monitoring data exceeds the set dead zone, an oscillation alarm judgment is performed based on the FFT algorithm to obtain an oscillation monitoring alarm result; when the oscillation monitoring type is sub / super synchronous oscillation or medium and high frequency oscillation, the oscillation monitoring judgment method is: an oscillation monitoring alarm method based on the combination of the master and substations.

[0022] According to a third aspect of the present invention, a computer device is provided, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of the above-mentioned power grid broadband oscillation monitoring and alarm method when executing the computer program.

[0023] According to a fourth aspect of the present invention, a computer-readable storage medium is provided, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the above-mentioned power grid broadband oscillation monitoring and alarm method are implemented.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] The broadband oscillation monitoring and alarm method of the power grid of the present invention adopts different oscillation monitoring and judgment methods for different oscillation monitoring types. Among them, for ultra-low frequency oscillation or low frequency oscillation, an oscillation monitoring and judgment method combining a time domain analysis method, an FFT algorithm and a Prony algorithm is adopted; for sub-synchronous oscillation, an oscillation monitoring and judgment method combining a time domain analysis method and an FFT algorithm is adopted; for sub- / super-synchronous oscillation or medium and high frequency oscillation, an oscillation monitoring and judgment method based on the combination of a master and a substation is adopted, which fully integrates the advantages of the time domain analysis method, the FFT algorithm and the Prony algorithm, and effectively solves the problem of misanalysis caused by frequency aliasing in data window selection and data analysis resampling of the pure Prony algorithm. In addition, since the Prony algorithm takes a long time to calculate, the method of the present invention effectively improves the efficiency of oscillation monitoring and alarming by improving the effectiveness of the Prony algorithm calculation. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 The flowchart of the method for monitoring and warning of broadband oscillation of a power grid according to an embodiment of the present invention is shown.

[0027] Figure 2 Detailed flowchart of the method for monitoring and warning of broadband oscillation of a power grid according to an embodiment of the present invention.

[0028] Figure 3 Schematic diagram of a method for calculating an oscillation monitoring value taking into account an oscillation dynamic process according to an embodiment of the present invention.

[0029] Figure 4 The figure is a structural block diagram of a power grid broadband oscillation monitoring and alarm system according to an embodiment of the present invention. DETAILED DESCRIPTION

[0030] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0031] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0032] The present invention is further described in detail below in conjunction with the accompanying drawings:

[0033] See also Figure 1 In one embodiment of the present invention, a method for monitoring and alarming broadband oscillations in a power grid is provided, specifically, a method for monitoring and alarming broadband oscillations in a power grid covering ultra-low frequency oscillations, low frequency oscillations, sub-synchronous oscillations, sub- / super-synchronous oscillations, and medium and high frequency oscillations based on the fusion of multiple methods in the time-frequency domain, which comprehensively applies the advantages of the FFT algorithm and the Prony algorithm of the time-domain analysis method to increase the practicality and effectiveness of the current broadband oscillation monitoring and alarming.

[0034] Specifically, the power grid broadband oscillation monitoring and alarming method of the present invention comprises the following steps:

[0035] S1: Obtain the oscillation monitoring type and oscillation monitoring data of the oscillation monitoring point.

[0036] S2: Based on the oscillation monitoring data, an oscillation monitoring alarm result is obtained by using an oscillation monitoring judgment method corresponding to the oscillation monitoring type.

[0037] Among them, when the oscillation monitoring type is ultra-low frequency oscillation or low frequency oscillation, the oscillation monitoring judgment method is: based on the time domain analysis method, determine whether the fluctuation of the oscillation monitoring data exceeds the set dead zone; and when the fluctuation of the oscillation monitoring data exceeds the set dead zone, based on the FFT algorithm, determine whether the oscillation monitoring data belongs to the frequency band of the currently monitored oscillation type; and when the oscillation monitoring data belongs to the frequency band of the currently monitored oscillation type, based on the Prony algorithm, perform oscillation alarm judgment to obtain the oscillation monitoring alarm result.

[0038] When the oscillation monitoring type is subsynchronous oscillation, the oscillation monitoring judgment method is: based on the time domain analysis method, determine whether the fluctuation of the oscillation monitoring data exceeds the set dead zone; and when the fluctuation of the oscillation monitoring data exceeds the set dead zone, perform oscillation alarm judgment based on the FFT algorithm to obtain the oscillation monitoring alarm result.

[0039] When the oscillation monitoring type is sub- / super-synchronous oscillation or medium- and high-frequency oscillation, the oscillation monitoring judgment method is: an oscillation monitoring judgment method based on the combination of the master and slave stations.

[0040] The broadband oscillation monitoring and alarm method of the power grid of the present invention adopts different oscillation monitoring and judgment methods for different oscillation monitoring types. Among them, for ultra-low frequency oscillation or low frequency oscillation, an oscillation monitoring and judgment method combining a time domain analysis method, an FFT algorithm and a Prony algorithm is adopted; for sub-synchronous oscillation, an oscillation monitoring and judgment method combining a time domain analysis method and an FFT algorithm is adopted; for sub- / super-synchronous oscillation or medium and high frequency oscillation, an oscillation monitoring and judgment method based on the combination of a master and a substation is adopted, which fully integrates the advantages of the time domain analysis method, the FFT algorithm and the Prony algorithm, and effectively solves the problem of misanalysis caused by frequency aliasing in data window selection and data analysis resampling of the pure Prony algorithm. In addition, since the Prony algorithm takes a long time to calculate, the method of the present invention effectively improves the efficiency of oscillation monitoring and alarming by improving the effectiveness of the Prony algorithm calculation.

[0041] The time domain analysis method directly analyzes the waveform of the oscillation signal that changes with time without spectrum conversion. It identifies and quantifies the oscillation phenomenon by observing the periodicity, amplitude change, and phase difference of the signal waveform. In oscillation monitoring, time domain analysis can intuitively display the dynamic process of oscillation, help to quickly capture the beginning and end of oscillation, and is an important means to preliminarily judge the type and intensity of oscillation. The FFT algorithm is an efficient algorithm that converts signals from the time domain to the frequency domain. In oscillation analysis, the FFT algorithm can reveal the frequency components and their distribution in the oscillation signal, especially the dominant frequency and harmonic components of the oscillation. Through the FFT spectrum diagram, the changing trend of the oscillation frequency can be clearly seen, which provides an important basis for in-depth analysis of the oscillation mechanism and formulation of control strategies. The Prony algorithm is a parameter estimation method that is particularly suitable for analyzing signals containing multiple exponentially decaying (or growing) sinusoidal wave components. In oscillation analysis, the Prony algorithm can accurately estimate the modal parameters of the oscillation, including oscillation frequency, damping ratio, and amplitude. These parameters are crucial for understanding the physical mechanism of oscillation, evaluating system stability, and designing effective control measures. The Prony algorithm generally has higher accuracy and resolution in extracting oscillation mode parameters than the FFT algorithm.

[0042] In one possible implementation, when the oscillation monitoring type and oscillation monitoring data are obtained, when the oscillation monitoring type is ultra-low frequency oscillation, low frequency oscillation or subsynchronous oscillation, the oscillation monitoring data is active power data; when the oscillation monitoring type is sub / supersynchronous oscillation or medium and high frequency oscillation, the oscillation monitoring data is the instantaneous oscillation power component or interharmonic current data sent by the substation.

[0043] Among them, all oscillation monitoring points carry out oscillation monitoring and alarm of ultra-low frequency oscillation, low frequency oscillation and sub-synchronous oscillation, and broadband oscillation monitoring points carry out oscillation monitoring and alarm of sub- / super-synchronous oscillation and medium and high frequency oscillation.

[0044] Specifically, whether the device contains the "SPN" identifier is marked as a broadband device; all oscillation monitoring points monitor ultra-low frequency oscillations, low frequency oscillations, and sub-synchronous oscillations; only oscillation monitoring points with broadband measurement equipment monitor sub- / super-synchronous oscillations and medium- and high-frequency oscillations. When obtaining the oscillation monitoring data of each oscillation monitoring point, the active power data in the PMU (Phasor Measurement Unit) data is used for ultra-low frequency oscillations, low frequency oscillations, and sub-synchronous oscillations; the amplitude and frequency corresponding to the instantaneous oscillation power component sent by the substation are directly obtained from the database for sub- / super-synchronous oscillations and medium- and high-frequency oscillations.

[0045] In one possible implementation, see Figure 2 The method for judging whether the fluctuation of the oscillation monitoring data exceeds the set dead zone based on the time domain analysis method includes: obtaining the current time window data according to the oscillation monitoring type and the oscillation monitoring data, and obtaining the difference between the maximum value of the oscillation monitoring data and the minimum value of the oscillation monitoring data in the current time window data; when the difference between the maximum value of the oscillation monitoring data and the minimum value of the oscillation monitoring data exceeds the set dead zone, the fluctuation of the oscillation monitoring data exceeds the set dead zone; when the difference between the maximum value of the oscillation monitoring data and the minimum value of the oscillation monitoring data does not exceed the set dead zone, the fluctuation of the oscillation monitoring data does not exceed the set dead zone, and returning to perform the oscillation monitoring judgment of the next time window data.

[0046] Specifically, the current time window data is obtained according to the oscillation monitoring type and the oscillation monitoring data, that is, the data within the set time period (current time window) of the oscillation monitoring data is obtained from the time series real-time library, and the current time window data can be preprocessed and filtered, and then the maximum value V of the oscillation monitoring data is obtained by using the time domain analysis method. max And the minimum value of oscillation monitoring data V min , and then obtain the maximum value V of the oscillation monitoring data max and oscillation monitoring data minimum value V min Then, the difference V between the maximum value of the oscillation monitoring data and the minimum value of the oscillation monitoring data is taken as the fluctuation indicator of the oscillation monitoring data. When the difference V between the maximum value of the oscillation monitoring data and the minimum value of the oscillation monitoring data exceeds the set dead zone, the fluctuation of the oscillation monitoring data exceeds the set dead zone; when the difference V between the maximum value of the oscillation monitoring data and the minimum value of the oscillation monitoring data does not exceed the set dead zone, the fluctuation of the oscillation monitoring data does not exceed the set dead zone, and the oscillation monitoring judgment of the next time window data is returned.

[0047] The dead zone is set according to the preset oscillation amplitude threshold of the oscillation monitoring point, and can generally be set to 20% of the preset oscillation amplitude threshold of the oscillation monitoring point.

[0048] In one possible implementation, see Figure 2 The method of judging whether the oscillation monitoring data belongs to the frequency band of the currently monitored oscillation type based on the FFT algorithm includes: obtaining the earlier moment of the maximum value of the oscillation monitoring data and the minimum value of the oscillation monitoring data in the current time window data to obtain the starting moment; obtaining the data after the starting moment in the current time window data to obtain the data to be analyzed; and performing spectrum analysis on the data to be analyzed using the FFT algorithm to obtain the frequency corresponding to the maximum amplitude of the data to be analyzed, and judging whether the frequency corresponding to the maximum amplitude belongs to the frequency band of the currently monitored oscillation type; when the frequency corresponding to the maximum amplitude belongs to the frequency band of the currently monitored oscillation type, the oscillation monitoring data belongs to the frequency band of the currently monitored oscillation type; when the frequency corresponding to the maximum amplitude does not belong to the frequency band of the currently monitored oscillation type, the oscillation monitoring data does not belong to the frequency band of the currently monitored oscillation type, and returns to perform oscillation monitoring judgment for the next time window data.

[0049] Specifically, taking ultra-low frequency oscillation as an example, if the frequency corresponding to the maximum amplitude of the data to be analyzed is not within the frequency band specified by the ultra-low frequency oscillation, then return to perform the next calculation. If the frequency corresponding to the maximum amplitude of the data to be analyzed is within the frequency band specified by the ultra-low frequency oscillation, it indicates that the oscillation monitoring point has ultra-low frequency oscillation, and then the next step of Prony algorithm calculation is performed.

[0050] In one possible implementation, see Figure 2 The oscillation alarm judgment based on the Prony algorithm to obtain the oscillation monitoring alarm result includes: analyzing the current time window data based on the Prony algorithm to obtain the dominant component amplitude and the dominant component frequency of the current time window data, and when the dominant component amplitude is greater than the difference between the maximum value of the oscillation monitoring data and the minimum value of the oscillation monitoring data, updating the dominant component amplitude to the difference between the maximum value of the oscillation monitoring data and the minimum value of the oscillation monitoring data; continuously obtaining the dominant component amplitude of a preset number of time window data and taking the average value to obtain the oscillation monitoring value; wherein, when continuously obtaining the dominant component amplitude of a preset number of time window data, when the current dominant component amplitude is less than half of the preset oscillation amplitude threshold of the oscillation monitoring point, returning to perform oscillation monitoring judgment for the next time window data.

[0051] When the oscillation monitoring value is greater than the preset oscillation amplitude threshold of the oscillation monitoring point, the oscillation monitoring alarm result is an oscillation alarm, and the start time of the oscillation is the current time minus

[0052] Optional, preset quantity Wnum Obtained by the following formula:

[0053]

[0054] Where N is the continuous frequency obtained by the preset oscillation time threshold of the oscillation monitoring point, f osc is the dominant component frequency of the current time window data, T slid The time window length of the time window data.

[0055] Specifically, the Prony algorithm is used to analyze the current time window data to obtain the amplitude and frequency corresponding to the dominant component, that is, the amplitude and frequency of the dominant component, and use them as the oscillation situation of the oscillation monitoring point in this time period. At this time, the dominant component frequency f osc As the oscillation frequency, the dominant component amplitude V cur The maximum value of the oscillation monitoring data V max and oscillation monitoring data minimum value V min If the dominant component amplitude V cur If it is greater than V, it will be corrected to V cur =V.

[0056] In this implementation, the oscillation time threshold preset at the oscillation monitoring point takes the continuous frequency number N as an example, and the number of time window data is limited by converting the continuous frequency number N into the number of windows, i.e., the number of operations. A circular array is set to store the amplitude of the dominant component of each time window data, and then the average value is taken after the preset number is met to obtain the oscillation monitoring value, and compared with the oscillation amplitude threshold preset at the oscillation monitoring point. When the oscillation monitoring value is greater than the oscillation amplitude threshold preset at the oscillation monitoring point, the oscillation monitoring alarm result is an oscillation alarm, which fully considers the dynamic process of the oscillation and can better reflect the oscillation event.

[0057] In a possible implementation, similar to the process of performing oscillation alarm judgment based on the Prony algorithm, the oscillation alarm judgment based on the FFT algorithm to obtain the oscillation monitoring alarm result includes: analyzing the current time window data based on the FFT algorithm to obtain the dominant component amplitude and the dominant component frequency of the current time window data, and when the dominant component amplitude is greater than the difference between the maximum value of the oscillation monitoring data and the minimum value of the oscillation monitoring data, updating the dominant component amplitude to the difference between the maximum value of the oscillation monitoring data and the minimum value of the oscillation monitoring data; continuously obtaining the dominant component amplitude of a preset number of time window data and taking the average value to obtain the oscillation monitoring value; wherein, when continuously obtaining the dominant component amplitude of a preset number of time window data, when the current dominant component amplitude is less than half of the oscillation amplitude threshold preset at the oscillation monitoring point, returning to perform oscillation monitoring judgment for the next time window data; when the oscillation monitoring value is greater than the oscillation amplitude threshold preset at the oscillation monitoring point, the oscillation monitoring alarm result is an oscillation alarm, and the start time of the oscillation is the current time minus

[0058] Optionally, the oscillation time threshold and the oscillation amplitude threshold preset at the oscillation monitoring point are set according to the voltage level and the oscillation monitoring type.

[0059] Specifically, the grid topology and equipment model information is obtained, including generators, lines, i.e., transformers, etc., the oscillation monitoring points are determined, and the voltage levels corresponding to the oscillation monitoring points are obtained. Then, thresholds are set for each oscillation monitoring point in combination with the oscillation monitoring type, including oscillation amplitude thresholds and oscillation time thresholds.

[0060] In a possible implementation, when the difference between the maximum value and the minimum value of the oscillation monitoring data exceeds the set dead zone, the first mark value of the oscillation monitoring point is 1; when the difference between the maximum value and the minimum value of the oscillation monitoring data does not exceed the set dead zone, the first mark value of the oscillation monitoring point is 0; when the frequency corresponding to the maximum amplitude falls within the frequency band of the currently monitored oscillation type, the second mark value of the oscillation monitoring point is 1; when the frequency corresponding to the maximum amplitude does not fall within the frequency band of the currently monitored oscillation type, the second mark value of the oscillation monitoring point is 0; when the amplitude of the dominant component is greater than the amplitude of the oscillation monitoring data When the difference between the maximum value and the minimum value of the oscillation monitoring data is greater than or equal to 1, the third mark value of the oscillation monitoring point is 1; when the first mark value of the oscillation monitoring point is 1 and the third mark value is 1, when the oscillation monitoring judgment of the time window data is performed, when the fluctuation of the oscillation monitoring data exceeds the set dead zone, the oscillation alarm judgment is directly performed based on the Prony algorithm to obtain the oscillation monitoring alarm result; wherein, when the amplitude of the dominant component of a preset number of time window data is continuously obtained, when the current amplitude of the dominant component is less than half of the preset oscillation amplitude threshold of the oscillation monitoring point, the first mark value, the second mark value and the third mark value of the oscillation monitoring point are all 0.

[0061] Specifically, by adopting the first tag value, the first tag value and the third tag value, when the first tag value is 1 and the third tag value is 1, the calculation process of the FFT algorithm can be omitted to save time.

[0062] In a possible implementation, when the current time window data is obtained according to the oscillation monitoring type and the oscillation monitoring data: when the oscillation monitoring type is an ultra-low frequency oscillation of 0.02 to 0.1 Hz, the time window length of the time window data is set to 100s, and the time window overlap length is 50s; when the oscillation monitoring type is a low frequency oscillation of 0.1 to 0.5 Hz, the time window length of the time window data is set to 20s, and the time window overlap length is 10s; when the oscillation monitoring type is a low frequency oscillation of 0.5 to 2.5 Hz, the time window length of the time window data is set to 10s, and the time window overlap length is 5s; when the oscillation monitoring type is a subsynchronous oscillation of 2.5 to 25 Hz, the time window length of the time window data is set to 10s, and the time window overlap length is 2s; when the oscillation monitoring type is a sub / supersynchronous oscillation or a medium or high frequency oscillation, the time window length of the time window data is set to 2s, and the time window overlap length is 0s.

[0063] Specifically, a frequency band division and time window data division strategy for the oscillation monitoring type are given in combination with the characteristics of the oscillation monitoring type, which greatly improves the performance efficiency.

[0064] In a possible implementation, a method based on the combination of the master and substation is used for the sub / supersynchronous oscillation or medium and high frequency oscillation of the broadband oscillation monitoring point. The amplitude and frequency corresponding to the instantaneous oscillation power component sent by the substation are directly obtained from the database, and the maximum amplitude and the corresponding frequency of the corresponding frequency band are obtained according to the frequency segmentation of the sub / supersynchronous oscillation and the medium and high frequency oscillation to perform oscillation monitoring and judgment. Considering the frequency fluctuation characteristics of the broadband oscillation, the initial frequency is used as the oscillation frequency until the oscillation amplitude is lower than 0.5 times the oscillation amplitude threshold, and the alarm is returned.

[0065] In a possible implementation, taking a low-frequency oscillation as an example, it is assumed that the oscillation amplitude threshold is set to V1. The oscillation active power data is as follows: Figure 3As shown, the current practice for judging the threshold and duration is to start counting when the amplitude exceeds the oscillation amplitude threshold, that is, the duration counting starts at t1. The practice in the present invention is that at time t0, the difference between the maximum and minimum values ​​obtained through time domain analysis within the set time window exceeds the oscillation amplitude threshold, so spectrum analysis is carried out based on the FFT algorithm; the obtained frequency is within the low-frequency oscillation range, and further analysis is carried out based on the Prony algorithm to obtain the oscillation frequency and oscillation amplitude V0. Since the value of the oscillation amplitude VO exceeds the set dead zone threshold, and the frequency meets the frequency range of low-frequency oscillation, the value of the oscillation amplitude V0 is included in the array. When the number of calculations reaches the set time requirement, the average value of the cyclic array is calculated, that is, the oscillation monitoring amplitude. At this time, if the oscillation monitoring amplitude exceeds V1, an oscillation alarm is given. From Figure 3 It can be seen that, compared with the previous methods, since the method of the present invention takes into account the dynamic process of oscillation, the alarm timing and judgment of oscillation are more in line with the actual situation, and the alarm can be issued in time.

[0066] The following are device embodiments of the present invention, which can be used to implement the method embodiments of the present invention. For details not disclosed in the device embodiments, please refer to the method embodiments of the present invention.

[0067] See also Figure 4 In another embodiment of the present invention, a power grid broadband oscillation monitoring and alarm system is provided, which can be used to implement the above-mentioned power grid broadband oscillation monitoring and alarm method. Specifically, the power grid broadband oscillation monitoring and alarm system includes a data acquisition module and an oscillation monitoring module.

[0068] Among them, the data acquisition module is used to obtain the oscillation monitoring type and oscillation monitoring data of the oscillation monitoring point; the oscillation monitoring module is used to obtain the oscillation monitoring alarm result based on the oscillation monitoring data through the oscillation monitoring judgment method corresponding to the oscillation monitoring type. Among them, when the oscillation monitoring type is ultra-low frequency oscillation or low frequency oscillation, the oscillation monitoring judgment method is: based on the time domain analysis method to judge whether the fluctuation of the oscillation monitoring data exceeds the set dead zone; and when the fluctuation of the oscillation monitoring data exceeds the set dead zone, based on the FFT algorithm to judge whether the oscillation monitoring data belongs to the frequency band range of the current monitored oscillation type; and when the oscillation monitoring data belongs to the frequency band range of the current monitored oscillation type, based on the Prony algorithm to perform oscillation alarm judgment to obtain the oscillation monitoring alarm result; when the oscillation monitoring type is sub-synchronous oscillation, the oscillation monitoring judgment method is: based on the time domain analysis method to judge whether the fluctuation of the oscillation monitoring data exceeds the set dead zone; and when the fluctuation of the oscillation monitoring data exceeds the set dead zone, based on the FFT algorithm to perform oscillation alarm judgment to obtain the oscillation monitoring alarm result; when the oscillation monitoring type is sub-synchronous oscillation / super-synchronous oscillation or medium and high frequency oscillation, the oscillation monitoring judgment method is: based on the oscillation monitoring alarm method combined with the master and substations.

[0069] All relevant contents of each step involved in the embodiment of the aforementioned power grid broadband oscillation monitoring and alarm method can be referred to the functional description of the functional modules corresponding to the power grid broadband oscillation monitoring and alarm system in the embodiment of the present invention, and will not be repeated here.

[0070] The division of modules in the embodiments of the present invention is schematic and is only a logical function division. There may be other division methods in actual implementation. In addition, each functional module in each embodiment of the present invention may be integrated into one processor, or may exist physically separately, or two or more modules may be integrated into one module. The above-mentioned integrated modules may be implemented in the form of hardware or in the form of software functional modules.

[0071] In another embodiment of the present invention, a computer device is provided, the computer device including a processor and a memory, the memory is used to store a computer program, the computer program includes program instructions, and the processor is used to execute 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 (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components, etc., which are the computing core and control core of the terminal, which are suitable for implementing one or more instructions, and are specifically suitable for loading and executing one or more instructions in the computer storage medium to implement the corresponding method flow or corresponding function; the processor described in the embodiment of the present invention can be used for the operation of the power grid broadband oscillation monitoring alarm method.

[0072] In another embodiment of the present invention, the present invention further provides a storage medium, specifically a computer-readable storage medium (Memory), which is a memory device in a computer device for storing programs and data. It can be understood that the computer-readable storage medium here can include both built-in storage media in the computer device and, of course, extended storage media supported by the computer device. The computer-readable storage medium provides a storage space, which stores the operating system of the terminal. In addition, one or more instructions suitable for being loaded and executed by the processor are also stored in the storage space, and these instructions can be one or more computer programs (including program codes). It should be noted that the computer-readable storage medium here can be a high-speed RAM memory or a non-volatile memory (non-volatile memory), such as at least one disk memory. The processor can load and execute one or more instructions stored in the computer-readable storage medium to implement the corresponding steps of the power grid broadband oscillation monitoring and alarm method in the above embodiment.

[0073] It will be appreciated by those skilled in the art that embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Furthermore, the present invention may take the form of a computer program product implemented 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.

[0074] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0075] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0076] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0077] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the relevant field should understand that the specific implementation methods of the present invention can still be modified or replaced by equivalents. Any modification or equivalent replacement that does not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A method for monitoring and warning of broadband oscillation in a power grid, characterized in that: include: Obtain the oscillation monitoring type and oscillation monitoring data of the oscillation monitoring point; Based on the oscillation monitoring data, an oscillation monitoring alarm result is obtained by using an oscillation monitoring judgment method corresponding to the oscillation monitoring type; Among them, when the oscillation monitoring type is ultra-low frequency oscillation or low frequency oscillation, the oscillation monitoring judgment method is: based on the time domain analysis method, judging whether the fluctuation of the oscillation monitoring data exceeds the set dead zone; and when the fluctuation of the oscillation monitoring data exceeds the set dead zone, judging whether the oscillation monitoring data belongs to the frequency band of the current monitored oscillation type based on the FFT algorithm; and when the oscillation monitoring data belongs to the frequency band of the current monitored oscillation type, performing oscillation alarm judgment based on the Prony algorithm to obtain the oscillation monitoring alarm result; When the oscillation monitoring type is subsynchronous oscillation, the oscillation monitoring judgment method is: judging whether the fluctuation of the oscillation monitoring data exceeds the set dead zone based on the time domain analysis method; and when the fluctuation of the oscillation monitoring data exceeds the set dead zone, performing oscillation alarm judgment based on the FFT algorithm to obtain the oscillation monitoring alarm result; When the oscillation monitoring type is sub- / super-synchronous oscillation or medium- and high-frequency oscillation, the oscillation monitoring judgment method is: an oscillation monitoring judgment method based on the combination of the master and slave stations.

2. The method for monitoring and warning of broadband oscillation of a power grid according to claim 1, characterized in that: When obtaining the oscillation monitoring type and oscillation monitoring data, when the oscillation monitoring type is ultra-low frequency oscillation, low frequency oscillation or subsynchronous oscillation, the oscillation monitoring data is active power data; when the oscillation monitoring type is sub / super synchronous oscillation or medium and high frequency oscillation, the oscillation monitoring data is the instantaneous oscillation power component or interharmonic current data sent by the substation; wherein all oscillation monitoring points perform oscillation monitoring and alarm for ultra-low frequency oscillation, low frequency oscillation and subsynchronous oscillation, and the broadband oscillation monitoring points perform oscillation monitoring and alarm for sub / super synchronous oscillation and medium and high frequency oscillation.

3. The method for monitoring and warning of broadband oscillation of a power grid according to claim 1, characterized in that: The method of judging whether the fluctuation of the oscillation monitoring data exceeds the set dead zone based on the time domain analysis method includes: Acquire the current time window data according to the oscillation monitoring type and the oscillation monitoring data, and acquire the difference between the maximum value of the oscillation monitoring data and the minimum value of the oscillation monitoring data in the current time window data; When the difference between the maximum value of the oscillation monitoring data and the minimum value of the oscillation monitoring data exceeds the set dead zone, the fluctuation of the oscillation monitoring data exceeds the set dead zone; When the difference between the maximum value of the oscillation monitoring data and the minimum value of the oscillation monitoring data does not exceed the set dead zone, the fluctuation of the oscillation monitoring data does not exceed the set dead zone, and the oscillation monitoring judgment of the next time window data is returned.

4. The method for monitoring and warning of broadband oscillation of a power grid according to claim 3, characterized in that: The method of judging whether the oscillation monitoring data belongs to the frequency band of the currently monitored oscillation type based on the FFT algorithm includes: Obtain the earlier time between the time when the oscillation monitoring data has the maximum value and the time when the oscillation monitoring data has the minimum value in the current time window data to obtain the starting time; Acquire the data after the start time in the current time window data to obtain the data to be analyzed; and perform spectrum analysis on the data to be analyzed using the FFT algorithm to obtain the frequency corresponding to the maximum amplitude of the data to be analyzed, and determine whether the frequency corresponding to the maximum amplitude belongs to the frequency band of the currently monitored oscillation type; When the frequency corresponding to the maximum amplitude falls within the frequency band of the currently monitored oscillation type, the oscillation monitoring data falls within the frequency band of the currently monitored oscillation type; when the frequency corresponding to the maximum amplitude does not fall within the frequency band of the currently monitored oscillation type, the oscillation monitoring data does not fall within the frequency band of the currently monitored oscillation type, and the data is returned to perform oscillation monitoring judgment for the next time window data.

5. The method for monitoring and warning of broadband oscillation of a power grid according to claim 4, characterized in that: The oscillation monitoring alarm result obtained by performing oscillation alarm judgment based on the Prony algorithm includes: Based on the Prony algorithm, the current time window data is analyzed to obtain the dominant component amplitude and dominant component frequency of the current time window data, and when the dominant component amplitude is greater than the difference between the maximum value of the oscillation monitoring data and the minimum value of the oscillation monitoring data, the dominant component amplitude is updated to the difference between the maximum value of the oscillation monitoring data and the minimum value of the oscillation monitoring data; Continuously obtain the amplitude of the dominant component of the preset number of time window data and take the average value to obtain the oscillation monitoring value; When the amplitude of the dominant component of the preset number of time window data is continuously obtained, when the current amplitude of the dominant component is less than half of the preset oscillation amplitude threshold of the oscillation monitoring point, return to perform oscillation monitoring judgment for the next time window data; the preset number W num Obtained by the following formula: Where N is the continuous frequency obtained by the preset oscillation time threshold of the oscillation monitoring point, f osc is the dominant component frequency of the current time window data, T slid is the time window length of the time window data; When the oscillation monitoring value is greater than the preset oscillation amplitude threshold of the oscillation monitoring point, the oscillation monitoring alarm result is an oscillation alarm, and the start time of the oscillation is the current time minus The oscillation alarm judgment based on the FFT algorithm to obtain the oscillation monitoring alarm result includes: Analyze the current time window data based on the FFT algorithm to obtain the dominant component amplitude and dominant component frequency of the current time window data, and when the dominant component amplitude is greater than the difference between the maximum value of the oscillation monitoring data and the minimum value of the oscillation monitoring data, update the dominant component amplitude to the difference between the maximum value of the oscillation monitoring data and the minimum value of the oscillation monitoring data; Continuously obtain the amplitude of the dominant component of the preset number of time window data and take the average value to obtain the oscillation monitoring value; When the amplitude of the dominant component of the preset number of time window data is continuously obtained, when the current amplitude of the dominant component is less than half of the preset oscillation amplitude threshold of the oscillation monitoring point, return to perform oscillation monitoring judgment for the next time window data; the preset number W num Obtained by the following formula: Where N is the continuous frequency obtained by the preset oscillation time threshold of the oscillation monitoring point, f osc is the dominant component frequency of the current time window data, T slid is the time window length of the time window data; When the oscillation monitoring value is greater than the preset oscillation amplitude threshold of the oscillation monitoring point, the oscillation monitoring alarm result is an oscillation alarm, and the start time of the oscillation is the current time minus Among them, the oscillation time threshold and oscillation amplitude threshold preset at the oscillation monitoring point are set according to the voltage level and oscillation monitoring type.

6. The method for monitoring and warning of broadband oscillation of a power grid according to claim 5, characterized in that: When the difference between the maximum value and the minimum value of the oscillation monitoring data exceeds the set dead zone, the first mark value of the oscillation monitoring point is 1; when the difference between the maximum value and the minimum value of the oscillation monitoring data does not exceed the set dead zone, the first mark value of the oscillation monitoring point is 0; when the frequency corresponding to the maximum amplitude falls within the frequency band of the currently monitored oscillation type, the second mark value of the oscillation monitoring point is 1; when the frequency corresponding to the maximum amplitude does not fall within the frequency band of the currently monitored oscillation type, the second mark value of the oscillation monitoring point is 0; When the amplitude of the dominant component is greater than the difference between the maximum value of the oscillation monitoring data and the minimum value of the oscillation monitoring data, the third marking value of the oscillation monitoring point is 1; When the first mark value of the oscillation monitoring point is 1 and the third mark value is 1, when the oscillation monitoring judgment of the time window data is performed, when the fluctuation of the oscillation monitoring data exceeds the set dead zone, the oscillation alarm judgment is directly performed based on the Prony algorithm to obtain the oscillation monitoring alarm result; wherein, when the dominant component amplitude of a preset number of time window data is continuously obtained, when the current dominant component amplitude is less than half of the preset oscillation amplitude threshold of the oscillation monitoring point, the first mark value, the first mark value and the third mark value of the oscillation monitoring point are all marked as 0.

7. The method for monitoring and warning of broadband oscillation of a power grid according to claim 3, characterized in that: When obtaining the current time window data according to the oscillation monitoring type and oscillation monitoring data: When the oscillation monitoring type is an ultra-low frequency oscillation of 0.02 to 0.1 Hz, the time window length of the time window data is set to 100 s, and the time window overlap length is 50 s; when the oscillation monitoring type is a low frequency oscillation of 0.1 to 0.5 Hz, the time window length of the time window data is set to 20 s, and the time window overlap length is 10 s; when the oscillation monitoring type is a low frequency oscillation of 0.5 to 2.5 Hz, the time window length of the time window data is set to 10 s, and the time window overlap length is 5 s; when the oscillation monitoring type is a subsynchronous oscillation of 2.5 to 25 Hz, the time window length of the time window data is set to 10 s, and the time window overlap length is 2 s; when the oscillation monitoring type is a sub / supersynchronous oscillation or a medium or high frequency oscillation, the time window length of the time window data is set to 2 s, and the time window overlap length is 0 s.

8. A power grid broadband oscillation monitoring and alarm system, characterized in that: include: A data acquisition module, used to acquire the oscillation monitoring type and oscillation monitoring data of the oscillation monitoring point; An oscillation monitoring module, used to obtain an oscillation monitoring alarm result based on the oscillation monitoring data by using an oscillation monitoring judgment method corresponding to the oscillation monitoring type; Among them, when the oscillation monitoring type is ultra-low frequency oscillation or low frequency oscillation, the oscillation monitoring judgment method is: based on the time domain analysis method, judging whether the fluctuation of the oscillation monitoring data exceeds the set dead zone; and when the fluctuation of the oscillation monitoring data exceeds the set dead zone, judging whether the oscillation monitoring data belongs to the frequency band of the current monitored oscillation type based on the FFT algorithm; and when the oscillation monitoring data belongs to the frequency band of the current monitored oscillation type, performing oscillation alarm judgment based on the Prony algorithm to obtain the oscillation monitoring alarm result; When the oscillation monitoring type is subsynchronous oscillation, the oscillation monitoring judgment method is: judging whether the fluctuation of the oscillation monitoring data exceeds the set dead zone based on the time domain analysis method; and when the fluctuation of the oscillation monitoring data exceeds the set dead zone, performing oscillation alarm judgment based on the FFT algorithm to obtain the oscillation monitoring alarm result; When the oscillation monitoring type is sub- / super-synchronous oscillation or medium- and high-frequency oscillation, the oscillation monitoring judgment method is: an oscillation monitoring alarm method based on the combination of the master and slave stations.

9. A computer device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, the steps of the power grid broadband oscillation monitoring and alarm method as claimed in any one of claims 1 to 7 are implemented.

10. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the steps of the power grid broadband oscillation monitoring and alarm method as claimed in any one of claims 1 to 7 are implemented.

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