Centralized station terminal with real-time data collection and analysis function

Abstract

The present invention relates to the field of ground fault detection technology, and specifically to a centralized station terminal with real-time data acquisition and analysis functions; differentially obtain a target time for a current effective value sequence; obtain a local quantity according to the historically connected differential value of the target time; obtain a local current segment and a corresponding spectrum diagram according to the target time and the local quantity; obtain a harmonic ratio coefficient according to the number of peak points and the amplitude of the peak points in the spectrum diagram of the target time and the historical adjacent target time; obtain a target coefficient according to the differential value and the harmonic ratio coefficient of the target time and the historical adjacent target time and perform clustering; obtain a detection reference value according to the discrete characteristics of the target coefficient in the clustering cluster. The present invention obtains an abnormal characteristic value according to the target coefficient at the current time and the detection reference value; performs high-resistance ground fault monitoring according to the abnormal characteristic value, thereby improving the accuracy of fault detection.

Description

Technical Field

[0001] The present invention relates to the technical field of ground fault detection, and in particular to a centralized station terminal with real-time data acquisition and analysis functions. Background Art

[0002] Centralized stations are advanced power automation equipment, usually used in substations or distribution stations; they can collect, process and analyze various operating data in the power system in real time, so as to timely discover potential short circuits, grounding and overcurrent faults in the operation of the power system, so as to ensure the safe, stable and efficient operation of the power system. In the existing centralized station identification process of grounding faults, high-resistance grounding faults are more common in small current grounding systems; due to the high grounding impedance, the current generated by high-resistance grounding faults is small, the change range is not large, and it may even be lower than the detection threshold of the terminal; if the detection threshold is set low, it is easy to be misdetected as a high-resistance grounding fault due to other factors. If the detection threshold is set high, it may be difficult to detect high-resistance grounding faults in time. Therefore, when detecting high-resistance grounding faults based on the detection threshold, missed detection or false detection may occur, resulting in low detection accuracy and even affecting the stable operation of the power system. Summary of the invention

[0003] In order to solve the technical problem of low accuracy in detecting high-resistance grounding faults based on the detection threshold, the present invention aims to provide a centralized station terminal with real-time data collection and analysis functions. The technical solution adopted is as follows:

[0004] A data acquisition module is used to obtain the current characteristic sequence and the corresponding current effective value sequence monitored at the current moment;

[0005] A data analysis module, used to differentiate the current effective value sequence to obtain differential values ​​at different moments; if the differential value at the current moment exceeds the constant 0, the moments at which the preset number of differential values ​​exceeding the constant 0 closest to the current moment and the current moment are located are used as target moments; a local quantity is obtained according to the difference characteristics between the historically connected differential values ​​at the target moment; a local current fragment is obtained in the current feature sequence according to the target moment and the local quantity;

[0006] A feature comparison module is used to obtain a spectrum diagram of a local current fragment at a target moment; obtain a harmonic ratio coefficient according to the difference characteristics of the number of peak points in the spectrum diagram between the target moment and the historical adjacent target moments and the difference characteristics of the amplitude of the peak points; obtain a target coefficient according to the difference characteristics of the differential value between the target moment and the historical adjacent target moments and the harmonic ratio coefficient; cluster the target coefficients of all target moments to obtain two clustering clusters; obtain a detection reference value according to the discrete characteristics of the target coefficients in the clustering clusters;

[0007] The abnormality detection module is used to obtain an abnormal characteristic value according to the difference characteristics between the target coefficient at the current moment and the detection reference value; and perform high-resistance grounding fault monitoring according to the abnormal characteristic value.

[0008] Furthermore, the step of obtaining the local quantity according to the difference characteristics between the historically connected difference values ​​at the target moment includes:

[0009] For any differential value within the preset historical neighborhood range of the target moment, calculate the absolute value of the difference between the arbitrary differential value and other differential values ​​at adjacent moments to obtain adjacent difference values ​​of the arbitrary differential value; calculate the average value of adjacent difference values ​​within the preset historical neighborhood range and perform negative correlation mapping and rounding through a preset function to obtain the local quantity.

[0010] Further, the step of acquiring a local current segment in the current feature sequence according to the target time and the local quantity includes:

[0011] In the current feature sequence, taking the target moment as a starting point, the local number of current data are selected in the historical time direction as the local current segment of the target moment.

[0012] Furthermore, the step of obtaining the harmonic ratio coefficient according to the difference characteristics of the number of peak points and the amplitude difference characteristics of the peak points in the spectrum diagram of the target moment and the historical adjacent target moment includes:

[0013] Calculate the sum of the amplitudes of the peak points in the spectrum diagram to obtain an energy intensity characteristic value; calculate the ratio of the energy intensity characteristic values ​​corresponding to the target moment and the historical adjacent target moment to obtain an energy ratio; calculate the ratio of the number of peak points in the spectrum diagram of the target moment and the historical adjacent target moment to obtain a quantity ratio; calculate the product of the energy ratio and the quantity ratio to obtain the harmonic ratio coefficient.

[0014] Furthermore, the step of obtaining the target coefficient according to the difference characteristics of the difference value between the target moment and the historical adjacent target moment and the harmonic ratio coefficient includes:

[0015] The ratio of the difference between the historical adjacent target moments and the target moment is calculated to obtain a difference ratio; and the product of the difference ratio and the harmonic ratio coefficient is calculated to obtain a target coefficient at the target moment.

[0016] Furthermore, the step of obtaining a detection reference value according to the discrete features of the target coefficients in the clusters includes:

[0017] The variance of the target coefficients at all target moments in the cluster is calculated to obtain a discrete degree value; and the average value of the target coefficients in the cluster with the smallest discrete degree value is calculated to obtain the detection reference value.

[0018] Furthermore, the step of obtaining the abnormal characteristic value according to the difference characteristic between the target coefficient at the current moment and the detection reference value includes:

[0019] The ratio of the target coefficient at the current moment to the detection reference value is calculated and normalized to obtain the abnormal characteristic value at the current moment.

[0020] Furthermore, the step of performing high-resistance grounding fault monitoring according to the abnormal characteristic value includes:

[0021] When the abnormal characteristic value exceeds the preset abnormal threshold, a high-resistance grounding fault occurs at the current moment.

[0022] The present invention has the following beneficial effects:

[0023] In the present invention, calculating the differential value at different times can determine the time when high-resistance grounding fault detection is required, and obtaining different target times can compare the harmonic characteristics according to the current fragments corresponding to the target times, thereby improving the accuracy of high-resistance grounding fault detection at the current time; obtaining the local quantity can adaptively select the current fragment length according to the current change characteristics, so that the obtained local current fragment can more accurately reflect the spectrum information at the target time. Obtaining the spectrum diagram of the local current fragment can reflect the harmonic characteristics of the current near the target time, so that normal current changes and high-resistance grounding faults can be distinguished according to the harmonic characteristics. Obtaining the harmonic ratio coefficient can reflect the difference in harmonic energy intensity and the difference in the number of harmonic signals between adjacent target times, further improving the accuracy of high-resistance grounding fault detection. Obtaining the target coefficient can improve the accuracy of the harmonic ratio coefficient and reduce the impact of current changes on it; obtaining the cluster cluster can accurately analyze the target coefficient under normal current changes, thereby making the detection reference value more accurate. Finally, the target coefficient at the current time is compared with the detection reference value to obtain an abnormal characteristic value, and the detection accuracy of the high-resistance grounding fault is improved according to the abnormal characteristic value. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions and advantages in the embodiments of the present invention or the prior art, the drawings required for use in the embodiments or the prior art descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0025] Figure 1A block diagram of a centralized station terminal with real-time data collection and analysis functions provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0026] In order to further explain the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the following is a detailed description of the specific implementation, structure, features and effects of a centralized station terminal with real-time data collection and analysis function proposed by the present invention in combination with the accompanying drawings and preferred embodiments. In the following description, different "one embodiment" or "another embodiment" does not necessarily refer to the same embodiment. In addition, specific features, structures or characteristics in one or more embodiments may be combined in any suitable form.

[0027] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

[0028] The following is a detailed description of a specific scheme of a centralized station terminal with real-time data collection and analysis function provided by the present invention in conjunction with the accompanying drawings.

[0029] See also Figure 1 , which shows a block diagram of a centralized station terminal with real-time data collection and analysis function provided by an embodiment of the present invention, the terminal includes the following modules:

[0030] The data acquisition module S1 is used to acquire the current characteristic sequence and the corresponding current effective value sequence monitored at the current moment.

[0031] In an embodiment of the present invention, the implementation scenario is the detection of a high-resistance grounding fault; first, the current characteristic sequence monitored at the current moment and the corresponding current effective value sequence are obtained; in an embodiment of the present invention, the current data of the historical 10 minutes including the current moment is obtained, and the acquisition frequency is 50 Hz, which can be set by the implementer according to the implementation scenario; after the current characteristic sequence corresponding to the current moment is acquired, the current effective value sequence is obtained by calculating the current effective value at each acquisition moment.

[0032] The data analysis module S2 is used to differentiate the current effective value sequence to obtain differential values ​​at different times; if the differential value at the current time exceeds the constant 0, the times at which the preset number of differential values ​​exceeding the constant 0 closest to the current time and the current time are located are used as target times; local quantities are obtained based on the difference characteristics between the historically connected differential values ​​at the target time; and local current fragments are obtained in the current feature sequence based on the target time and the local quantities.

[0033] A high-resistance grounding fault refers to a fault in which a phase line in a power system is connected to the ground through a high resistance. Because high impedance limits the flow of current, this fault will result in a small fault current, making it difficult to accurately identify a high-resistance grounding fault by directly analyzing the current change. However, a high-impedance grounding point can easily cause current to flow nonlinearly through the grounding point, thereby generating a non-sinusoidal current signal, causing the current waveform to be distorted and introducing harmonic components; therefore, a high-resistance grounding fault can be identified through the current spectrum information.

[0034] If the effective current value corresponding to the current moment is greater than the effective current value of the previous moment, it means that the current increases and a high-resistance grounding fault may occur. Therefore, it is necessary to further analyze whether a high-resistance grounding fault occurs at the current moment. Therefore, the current effective value sequence is differentiated to obtain the differential values ​​at different moments. If the differential value at the current moment exceeds the constant 0, it is necessary to further determine whether a high-resistance grounding fault occurs at the current moment; because the current will also fluctuate slightly under normal circumstances, but obvious harmonics will not easily appear, and then the moment at which the preset number of differential values ​​exceeding the constant 0 closest to the current moment and the current moment are used as the target moment, and then the different target moments are compared and analyzed. In the embodiment of the present invention, the preset number is 50, and the implementer can determine it according to the implementation scenario. If the current effective value sequence does not meet the preset number of target moments, the actual number of target moments is used for subsequent analysis. If the differential value at the current moment does not exceed the constant 0, the high-resistance grounding fault is not detected at the current moment.

[0035] Furthermore, the local current fragments before the target moment can be analyzed, and the frequency spectrum characteristics of the current fragments before different target moments can be used as a reference to improve the detection accuracy at the current moment. If the local current sequence before the target moment changes greatly, it is necessary to select a shorter current fragment for analysis, which can not only improve the efficiency of Fourier transform and make the detection of high-resistance grounding faults more timely, but also avoid selecting too long fragments and affecting the accuracy of local current change analysis. If the local current sequence changes less, it is necessary to select a longer current fragment for analysis to obtain more change information; therefore, the local quantity can be obtained based on the difference characteristics between the historically connected differential values ​​at the target moment.

[0036] Preferably, in an embodiment of the present invention, the step of obtaining local data includes: for any differential value within the preset historical neighborhood range of the target moment, calculating the absolute value of the difference between the arbitrary differential value and other differential values ​​at adjacent moments, and obtaining the adjacent difference value of the arbitrary differential value; when the adjacent difference value is larger, it means that the current change is more obvious, and detection and analysis can be performed based on a shorter current segment, and the adjacent moment is the previous moment of the arbitrary differential value. In an embodiment of the present invention, the preset historical neighborhood range is the 20 differential values ​​before the target moment, and the implementer can determine it by himself according to the implementation scenario. If the number of differential values ​​before the target moment does not meet the preset historical neighborhood range, the actual number of differential values ​​is used for calculation. The average value of the adjacent difference values ​​within the preset historical neighborhood range is calculated and negatively correlated mapped and rounded through a preset function to obtain a local number; when the adjacent difference value within the preset historical neighborhood range is larger, it means that the current change in the range is more obvious, and detection and analysis can be performed based on a shorter current segment; if the adjacent difference value is smaller, it means that the current in the range is more stable, and a longer current segment is required for detection and analysis to increase the amount of change information. In an embodiment of the present invention, the preset function is , y is the mapping value, x is the average value of the adjacent difference values ​​within the preset historical neighborhood, k is 5.2, and b is 100; implementers can determine it according to the implementation scenario.

[0037] Furthermore, local current fragments can be obtained in the current feature sequence according to the target time and the local quantity, specifically including: starting from the target time in the current feature sequence, selecting the local quantity of current data in the historical time direction as the local current fragment of the target time; if the local quantity of current data is not satisfied, the actual quantity of current data is used as the local current fragment. After obtaining the local current fragments at different target times, the abnormal situation at the current moment can be analyzed according to the spectrum characteristics of different local current fragments.

[0038] The feature comparison module S3 is used to obtain the spectrum of the local current fragment at the target moment; obtain the harmonic ratio coefficient according to the difference characteristics of the number of peak points and the amplitude difference characteristics of the peak points in the spectrum of the target moment and the historical adjacent target moments; obtain the target coefficient according to the difference characteristics of the differential value between the target moment and the historical adjacent target moments and the harmonic ratio coefficient; cluster the target coefficients of all target moments to obtain two clustering clusters; obtain the detection reference value according to the discrete characteristics of the target coefficients in the clustering clusters.

[0039] First, the spectrum diagram of the local current segment at the target moment is obtained, and the corresponding spectrum diagram can be obtained using the existing Fourier transform. The specific steps will not be repeated. Under normal circumstances, the harmonic information in the power grid may change normally within a certain range with the change of current. When a high-resistance grounding fault occurs in the power grid, the change of the harmonic information in the current is significantly different from the normal change. When there is a harmonic component signal in the current information, there will be other peak points in the spectrum diagram in addition to the peak point corresponding to the fundamental signal; the amplitude corresponding to the peak point represents the energy intensity of the corresponding frequency component signal in the local current segment. In a normal current signal, the component information and energy intensity in the current have a certain stability; therefore, the harmonic ratio coefficient can be obtained based on the difference characteristics of the number of peak points in the spectrum diagram of the target moment and the historical adjacent target moment, and the difference characteristics of the amplitude of the peak points.

[0040] Preferably, in an embodiment of the present invention, the step of obtaining the harmonic ratio coefficient includes: calculating the sum of the amplitudes of the peak points in the spectrum diagram to obtain an energy intensity characteristic value; when the energy intensity characteristic value is larger, it means that there are more harmonic signals and the energy intensity is larger. Calculate the ratio of the energy intensity characteristic values ​​corresponding to the target moment and the historical adjacent target moment to obtain the energy ratio; when the energy ratio is larger, it means that the harmonic energy intensity of the local current segment at the target moment is greater than the harmonic energy intensity of the local current segment at the historical adjacent target moment. Calculate the ratio of the number of peak points in the spectrum diagram of the target moment and the historical adjacent target moment to obtain the quantity ratio; when the quantity ratio is larger, it means that the local current segment at the target moment has more harmonic signals than the local current segment at the historical adjacent target moment. Calculate the product of the energy ratio and the quantity ratio to obtain the harmonic ratio coefficient; when the harmonic ratio coefficient is larger, it means that the harmonic energy intensity and the number of harmonic signals at the target moment are greater than the historical adjacent target moments, and the target moment is more likely to have a high-resistance grounding fault; when the harmonic ratio coefficient is closer to 1, it means that the harmonic characteristics of adjacent target moments are more similar; the harmonic ratio coefficient is not calculated for the first target moment. The formulas for obtaining the harmonic ratio coefficient include:

[0041]

[0042] In the formula, Represents the harmonic ratio coefficient at the rth target moment, Indicates the number of peak points in the spectrum graph corresponding to the rth target moment, Indicates The number of peak points in the spectrum graph corresponding to the target moment, Indicates the amplitude of the nth peak point in the spectrum graph corresponding to the rth target moment, Represents the energy intensity characteristic value of the spectrum graph corresponding to the rth target moment, Indicates The energy intensity characteristic value of the spectrum graph corresponding to the target moment, represents the energy ratio, Indicates the quantity ratio.

[0043] Furthermore, the harmonic ratio coefficient is obtained through the spectrum diagram of the local current fragment corresponding to the adjacent target moment, but when the current information changes greatly, the corresponding harmonic characteristics may also change more, resulting in the harmonic ratio coefficient being unable to accurately analyze the high-resistance grounding fault; therefore, it is necessary to correct the harmonic ratio coefficient to reduce the difference in harmonic information calculation caused by the different current change amplitudes, so the target coefficient is obtained according to the difference characteristics and harmonic ratio coefficient of the differential value between the target moment and the historical adjacent target moment; preferably, in an embodiment of the present invention, the step of obtaining the target coefficient includes: calculating the ratio of the differential value between the historical adjacent target moment and the target moment, and obtaining the differential ratio; when the differential ratio is larger, it means that the current change amplitude at the historical adjacent target moment is larger, then the harmonic information at the historical adjacent target moment may be more obvious, making the value of the harmonic ratio coefficient at the target moment smaller, so it needs to be corrected according to the differential ratio. Calculate the product of the differential ratio and the harmonic ratio coefficient to obtain the target coefficient at the target moment; when the differential ratio is larger, the degree of correction is greater, and the target coefficient is larger than the original harmonic ratio coefficient to avoid the harmonic ratio coefficient being too small to affect subsequent detection.

[0044] After obtaining the target coefficients of all target moments corresponding to the current moment, a reference value can be selected according to the distribution characteristics of the target coefficients. Under normal current changes, the target coefficients of most target moments are similar; while the target coefficients under abnormal current conditions are relatively discrete; therefore, clustering can be performed based on the target coefficients of all target moments to obtain two cluster clusters; in an embodiment of the present invention, clustering is performed using the existing K-means clustering algorithm, and the specific clustering steps are not repeated. One cluster cluster is the distribution of target coefficients of normal adjacent target moments, and the other cluster cluster is the distribution of target coefficients of abnormal adjacent target moments. Further, a detection reference value can be obtained based on the discrete characteristics of the target coefficients in the cluster cluster; preferably, in an embodiment of the present invention, the step of obtaining the detection reference value includes: calculating the variance of the target coefficients of all target moments in the cluster cluster to obtain a discrete degree value; the smaller the discrete degree value, the more similar the target coefficients are, and the more likely the cluster cluster is a cluster cluster of a normal target moment. The average value of the target coefficient in the cluster with the smallest discrete degree value is calculated to obtain the detection reference value; the detection reference value reflects the ratio characteristics of the harmonic information of the target moment and the historical adjacent target moment when the target moment occurs, and then the high-resistance grounding fault can be detected according to the detection reference value.

[0045] The abnormality detection module S4 is used to obtain an abnormality characteristic value according to the difference characteristics between the target coefficient at the current moment and the detection reference value; and perform high-resistance grounding fault monitoring according to the abnormality characteristic value.

[0046] After obtaining the detection reference value, the target coefficient at the current moment can be compared with the detection reference value to determine whether a high-resistance grounding fault occurs at the current moment. According to module S3, the larger the target coefficient is, the more likely it is that a high-resistance grounding fault will occur. At the same time, if the target coefficient at the current moment is larger than the detection reference value, it means that the possibility of a high-resistance grounding fault occurring at the current moment is greater; therefore, the abnormal characteristic value can be obtained based on the difference characteristics between the target coefficient at the current moment and the detection reference value.

[0047] Preferably, in an embodiment of the present invention, the step of obtaining an abnormal characteristic value includes: calculating the ratio of the target coefficient at the current moment to the detection reference value and normalizing it to obtain the abnormal characteristic value at the current moment; when the abnormal characteristic value is larger, it means that a high-resistance grounding fault is more likely to occur at the current moment. Then, high-resistance grounding fault monitoring can be performed according to the abnormal characteristic value, specifically including: when the abnormal characteristic value exceeds the preset abnormal threshold, a high-resistance grounding fault occurs at the current moment; in an embodiment of the present invention, the preset abnormal threshold is 0.6, which can be determined by the implementer according to the implementation scenario. So far, firstly, whether to detect a high-resistance grounding fault is determined based on the current differential value at the current moment, and then the ratio characteristics of the harmonic information at adjacent target moments are determined through the local current sequence before the target moment, and finally the target coefficient at the current moment is compared with the detection reference value, thereby improving the accuracy of high-resistance grounding fault detection.

[0048] In summary, the embodiment of the present invention provides a centralized station terminal with real-time data collection and analysis functions; differentially obtains the target time for the current effective value sequence; obtains the local quantity according to the historically connected differential value at the target time; obtains the local current fragment and the corresponding spectrum diagram according to the target time and the local quantity; obtains the harmonic ratio coefficient according to the number of peak points and the amplitude of the peak points in the spectrum diagram of the target time and the historical adjacent target time; obtains the target coefficient according to the differential value and the harmonic ratio coefficient between the target time and the historical adjacent target time and clusters; obtains the detection reference value according to the discrete characteristics of the target coefficient in the cluster cluster. The present invention obtains an abnormal characteristic value according to the target coefficient at the current time and the detection reference value; performs high-resistance grounding fault monitoring according to the abnormal characteristic value, thereby improving the accuracy of fault detection.

[0049] It should be noted that the sequence of the above embodiments of the present invention is only for description and does not represent the advantages and disadvantages of the embodiments. The processes depicted in the accompanying drawings do not necessarily require the specific order or continuous order shown to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0050] The various embodiments in this specification are described in a progressive manner, and the same or similar parts between the various embodiments can be referenced to each other, and each embodiment focuses on the differences from other embodiments.

Claims

1. A centralized station terminal with real-time data collection and analysis function, characterized in that: The centralized station terminal includes the following modules: A data acquisition module is used to obtain the current characteristic sequence and the corresponding current effective value sequence monitored at the current moment; A data analysis module, used to differentiate the current effective value sequence to obtain differential values ​​at different moments; if the differential value at the current moment exceeds the constant 0, the moments at which the preset number of differential values ​​exceeding the constant 0 closest to the current moment and the current moment are located are used as target moments; a local quantity is obtained according to the difference characteristics between the historically connected differential values ​​at the target moment; a local current fragment is obtained in the current feature sequence according to the target moment and the local quantity; A feature comparison module is used to obtain a spectrum diagram of a local current fragment at a target moment; obtain a harmonic ratio coefficient according to the difference characteristics of the number of peak points in the spectrum diagram between the target moment and the historical adjacent target moments and the difference characteristics of the amplitude of the peak points; obtain a target coefficient according to the difference characteristics of the differential value between the target moment and the historical adjacent target moments and the harmonic ratio coefficient; cluster the target coefficients of all target moments to obtain two clustering clusters; obtain a detection reference value according to the discrete characteristics of the target coefficients in the clustering clusters; An abnormality detection module, used for obtaining an abnormality characteristic value according to a difference characteristic between a target coefficient at a current moment and the detection reference value; Performing high-resistance grounding fault monitoring according to the abnormal characteristic value; The step of obtaining the local quantity according to the difference characteristics between the historically connected difference values ​​at the target moment comprises: For any differential value within a preset historical neighborhood range of the target moment, calculate the absolute value of the difference between the arbitrary differential value and other differential values ​​at adjacent moments to obtain adjacent differential values ​​of the arbitrary differential value; calculate the average value of adjacent differential values ​​within the preset historical neighborhood range and perform negative correlation mapping and rounding through a preset function to obtain the local quantity; The step of obtaining the harmonic ratio coefficient according to the difference characteristics of the number of peak points and the amplitude difference characteristics of the peak points in the frequency spectrum of the target moment and the historical adjacent target moments comprises: Calculate the sum of the peak point amplitudes in the spectrum graph to obtain an energy intensity characteristic value; calculate the ratio of the energy intensity characteristic values ​​corresponding to the target moment and the historical adjacent target moment to obtain an energy ratio; calculate the ratio of the number of peak points in the spectrum graph of the target moment and the historical adjacent target moment to obtain a quantity ratio; calculate the product of the energy ratio and the quantity ratio to obtain the harmonic ratio coefficient; The step of obtaining the target coefficient according to the difference characteristics of the difference value between the target moment and the historical adjacent target moments and the harmonic ratio coefficient comprises: Calculating the ratio of the difference between the historical adjacent target moments and the target moment to obtain a difference ratio; calculating the product of the difference ratio and the harmonic ratio coefficient to obtain a target coefficient at the target moment; The step of obtaining a detection reference value according to the discrete features of the target coefficients in the clusters comprises: The variance of the target coefficients at all target moments in the cluster is calculated to obtain a discrete degree value; and the average value of the target coefficients in the cluster with the smallest discrete degree value is calculated to obtain the detection reference value.

2. A centralized station terminal with real-time data collection and analysis function according to claim 1, characterized in that: The step of acquiring a local current segment in the current feature sequence according to the target time and the local quantity comprises: In the current feature sequence, taking the target moment as a starting point, the local number of current data are selected in the historical time direction as the local current segment of the target moment.

3. The centralized station terminal with real-time data collection and analysis function according to claim 1 is characterized in that: The step of obtaining the abnormal characteristic value according to the difference characteristic between the target coefficient at the current moment and the detection reference value comprises: The ratio of the target coefficient at the current moment to the detection reference value is calculated and normalized to obtain the abnormal characteristic value at the current moment.

4. The centralized station terminal with real-time data collection and analysis function according to claim 1 is characterized in that: The step of performing high-resistance grounding fault monitoring according to the abnormal characteristic value comprises: When the abnormal characteristic value exceeds the preset abnormal threshold, a high-resistance grounding fault occurs at the current moment.

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