A non-contact transmission line fault monitoring method and device

Abstract

The present application relates to the technical field of electric variable measurement, and specifically to a non-contact transmission line fault monitoring method and device, the method comprising: collecting various three-phase electrical parameters of the transmission line at various times; dividing any type of single-phase electrical parameters at all times into various periods, forming all the single-phase electrical parameters of any type in each period into various single-phase electrical parameter sequences, determining the jitter coefficient and fundamental frequency deviation coefficient of the single-phase electrical parameter sequence of each period; obtaining the distortion coefficient of the single-phase electrical parameter sequence of each period; determining the proximity distinction and peak distinction of the single-phase electrical parameter sequence of each period; obtaining the difference coefficient of the single-phase electrical parameter sequence of each period; using the fusion result of the difference coefficient of any type of three-phase electrical parameters of each period as the local difference of any type of three-phase electrical parameters of each period; and obtaining the fault monitoring result of the transmission line. Thereby improving the accuracy of the transmission line fault monitoring.

Description

Technical Field

[0001] The present application relates to the technical field of electrical variable measurement, and in particular to a non-contact transmission line fault monitoring method and device. Background Art

[0002] As an important part of the power grid, transmission lines are an important bridge to ensure the transmission of electric energy from power plants to distribution networks and even end users. The monitoring of their operating status and fault diagnosis are crucial to ensure the safe, stable and economical operation of the power system. Currently, non-contact measurement technology has been widely used in the field of transmission line monitoring due to its advantages such as safety, flexibility and high efficiency.

[0003] Since the non-contact measurement method has a high degree of dependence on the stability of the spatial coupling capacitance of the sensor, many uncertainties are introduced into the measurement. In practical applications, the measurement accuracy is often affected by the surrounding environment, such as changes in temperature and humidity, resulting in small fluctuations or abnormal amplitudes in the collected three-phase current and three-phase voltage. Existing methods are easily disturbed by these unstable conditions during the fault diagnosis process, misjudging the detected fluctuations or abnormal amplitudes as faults, resulting in low accuracy in transmission line fault monitoring. Summary of the invention

[0004] In order to solve the above technical problems, the purpose of this application is to provide a non-contact transmission line fault monitoring method and device, and the technical solutions adopted are as follows:

[0005] In a first aspect, an embodiment of the present application provides a non-contact power transmission line fault monitoring method, the method comprising the following steps:

[0006] Collect various three-phase electrical parameters of the transmission line at all times;

[0007] Divide any type of single-phase electrical parameters at all times into periods, form all the single-phase electrical parameters of any type in each period into single-phase electrical parameter sequences, and determine the jitter coefficient of the single-phase electrical parameter sequence of each period based on the distribution difference between the high-frequency component and the low-frequency component in each single-phase electrical parameter sequence;

[0008] Analyze the correlation between the single-phase electrical parameter sequence of each cycle and its frequency component, as well as the distribution of the frequency component, to determine the fundamental frequency deviation coefficient of the single-phase electrical parameter sequence of each cycle; combine the jitter coefficient and the fundamental frequency deviation coefficient to determine the distortion coefficient of the single-phase electrical parameter sequence of each cycle; analyze the difference between the distortion coefficient of each cycle and its adjacent cycles to determine the adjacent distinction of the single-phase electrical parameter sequence of each cycle;

[0009] Analyze the difference in amplitude change of the single-phase electrical parameter sequence of each cycle and its adjacent cycles to determine the peak difference of the single-phase electrical parameter sequence of each cycle; combine the adjacent difference and the peak difference to determine the difference coefficient of the single-phase electrical parameter sequence of each cycle; and use the fusion result of the difference coefficient of any type of three-phase electrical parameters of each cycle as the local difference of any type of three-phase electrical parameters of each cycle;

[0010] The discrete degrees of the local differences of various three-phase electrical parameters in all cycles are analyzed to obtain the fault characteristic values ​​of the transmission line and the fault monitoring results of the transmission line.

[0011] In one embodiment, the construction of the jitter coefficient includes:

[0012] The Hankel matrix of each single-phase electrical parameter sequence is obtained, the cumulative sum of the differences between each singular value corresponding to the Hankel matrix and all remaining singular values ​​is calculated, and the average of all the cumulative sums of each single-phase electrical parameter sequence is used as the jitter coefficient.

[0013] In one embodiment, the determination of the fundamental frequency deviation coefficient includes:

[0014] The discreteness of the harmonic component of the single-phase electrical parameter sequence of each period is calculated, recorded as the first discreteness; the similarity between the single-phase electrical parameter sequence of each period and its fundamental component is calculated, and the difference between the first discreteness and the similarity is used as the fundamental frequency deviation coefficient.

[0015] In one embodiment, the distortion coefficient is the product of the jitter coefficient and the baseband deviation coefficient.

[0016] In one embodiment, the neighboring distinctiveness is the average of the differences between the distortion coefficients of each period and its neighboring periods.

[0017] In one embodiment, the determination of the peak distinctiveness includes:

[0018] The peak values ​​of the single-phase electrical parameter sequence of each cycle are obtained, the sum of the differences between the peak values ​​of each cycle and the peak values ​​of the adjacent cycles is calculated, and the fusion result of all the sum values ​​of each cycle is used as the peak distinction of the single-phase electrical parameter sequence of each cycle.

[0019] In one embodiment, the difference coefficient is the product of the neighboring distinction and the peak distinction.

[0020] In one embodiment, obtaining the fault monitoring result of the power transmission line includes:

[0021] The discrete degree of the local difference of various types of three-phase electrical parameters of all cycles is recorded as a second discreteness, and the fusion result of the second discreteness of all types of three-phase electrical parameters is used as a fault characteristic value of the transmission line;

[0022] A fault monitoring result of the transmission line is obtained based on the fault characteristic value.

[0023] In one embodiment, if the normalized value of the fault characteristic value is greater than or equal to a preset fault threshold, it is determined that a ground fault occurs in the transmission line; otherwise, it is determined that the transmission line is normal.

[0024] In a second aspect, an embodiment of the present application further provides a contactless power transmission line fault monitoring device, comprising a memory, a processor, and a computer program stored in the memory and running on the processor, wherein the processor implements the steps of any one of the above methods when executing the computer program.

[0025] This application has at least the following beneficial effects:

[0026] The present application collects various three-phase electrical parameters at each moment of the transmission line; divides any type of single-phase electrical parameters at all moments into periods, and combines all the single-phase electrical parameters of any type in each period into single-phase electrical parameter sequences, and determines the jitter coefficient of the single-phase electrical parameter sequence of each period based on the distribution difference between the high-frequency component and the low-frequency component in each single-phase electrical parameter sequence; the jitter coefficient reflects the degree of rapid jitter of the single-phase electrical parameter sequence, and reflects the possibility of a grounding fault in the transmission line; further, the correlation between the single-phase electrical parameter sequence of each period and its frequency component, as well as the distribution of the frequency component, is analyzed to determine the fundamental frequency deviation coefficient of the single-phase electrical parameter sequence of each period; the fundamental frequency deviation coefficient reflects the degree to which the elements in the single-phase electrical parameter sequence conform to the non-periodic distribution, and reflects the distribution characteristics of the fundamental component and the harmonic component in the single-phase electrical parameter sequence, which is used as the basis for determining the occurrence of a grounding fault in the transmission line; combining the jitter coefficient and the fundamental frequency deviation coefficient, the distortion coefficient of the single-phase electrical parameter sequence of each period is determined; the distortion coefficient further reflects the possibility of a grounding fault in the transmission line, The reliability of transmission line fault monitoring is improved; then, the difference between the distortion coefficients of each cycle and its adjacent cycles is analyzed to determine the proximity distinction of the single-phase electrical parameter sequence of each cycle; the difference between the amplitude changes of the single-phase electrical parameter sequence of each cycle and its adjacent cycles is analyzed to determine the peak distinction of the single-phase electrical parameter sequence of each cycle; the difference coefficient of the single-phase electrical parameter sequence of each cycle is determined by combining the proximity distinction and the peak distinction; the difference coefficient reflects the degree of drastic change of the single-phase electrical parameter data of each cycle compared with the single-phase electrical parameter data of the adjacent cycles, and also reflects the degree of abnormality of the single-phase electrical parameter sequence of each cycle, that is, the possibility of transmission line failure; finally, the fusion result of the difference coefficient of any type of three-phase electrical parameters of each cycle is used as the local difference of any type of three-phase electrical parameters of each cycle; the discrete degree of the local difference of various types of three-phase electrical parameters of all cycles is analyzed to obtain the fault monitoring result of the transmission line, thereby improving the accuracy of transmission line fault monitoring and making up for the defect of low accuracy of existing monitoring methods. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions and advantages in the embodiments of the present application 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 application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0028] Figure 1 A flowchart of a non-contact power transmission line fault monitoring method provided in one embodiment of the present application;

[0029] Figure 2Construct a flow chart for transmission line fault eigenvalues. DETAILED DESCRIPTION

[0030] In order to further explain the technical means and effects adopted by the present application to achieve the predetermined invention purpose, the following is a detailed description of a non-contact power transmission line fault monitoring method and device proposed in accordance with the present application, its specific implementation, structure, features and effects, 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.

[0031] 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 application belongs.

[0032] The following is a detailed description of a non-contact power transmission line fault monitoring method and device provided by the present application in conjunction with the accompanying drawings.

[0033] See also Figure 1 , which shows a step flow chart of a non-contact power transmission line fault monitoring method provided by an embodiment of the present application, the method comprising the following steps:

[0034] S1, collects various three-phase electrical parameters of the transmission line at each time and performs preprocessing.

[0035] High-voltage power grids generally adopt a neutral point grounding operation mode, and single-phase ground short circuit is one of the most common faults in power transmission line faults. This embodiment uses a non-contact current sensor and a non-contact voltage sensor to respectively collect the three-phase current and three-phase voltage at each moment in the power transmission line, and the three-phase current and three-phase voltage are recorded as three-phase electrical parameters. The three-phase current at each moment is respectively composed of three single-phase currents, and the three-phase voltage is also respectively composed of three single-phase voltages. The single-phase current and single-phase voltage are both recorded as single-phase electrical parameters. This embodiment sets the time interval for data collection to 0.1 milliseconds and the collection time to 1 second. The implementer can set them according to the actual situation, and this embodiment does not limit it here.

[0036] It should be noted that missing data may occur during the collection process due to interference from external factors or instruments. For each single-phase current and single-phase voltage data at each moment, this embodiment uses the median filling method to fill the missing values. The implementer may also use other existing data filling methods for filling, which is not limited in this embodiment. So far, this embodiment has obtained three single-phase current data and three single-phase voltage data at each moment.

[0037] S2, divide any type of single-phase electrical parameters at all times into periods, and organize all the single-phase electrical parameters of any type in each period into single-phase electrical parameter sequences, and determine the jitter coefficient of the single-phase electrical parameter sequence of each period based on the distribution difference between the high-frequency component and the low-frequency component in each single-phase electrical parameter sequence.

[0038] In the power grid operating environment, the non-contact measurement method of voltage and current can ensure the insulation integrity of the distribution network line without damaging the original structure of the line. In the process of measuring three-phase voltage and three-phase current, it may be interfered by environmental factors, resulting in slight fluctuations or abnormal amplitudes in some single-phase voltage and current data, affecting the accuracy of subsequent single-phase ground short-circuit fault diagnosis. Single-phase ground short circuit may be caused by insulation damage and overvoltage breakdown, resulting in different degrees of obvious distortion of each collected single-phase current and voltage data. Therefore, this embodiment analyzes the waveform changes of each single-phase current and voltage data.

[0039] When a ground fault occurs in the transmission line, the single-phase current data will show obvious jitter of non-sinusoidal waveform. In order to analyze the change characteristics of data in the local range, taking any single-phase current as an example, the single-phase current at all times is divided into cycles. Since the frequency of the current in the transmission line is usually 50HZ, the length of the cycle is set to 0.02 seconds in this embodiment. The implementer can set it according to the actual situation, and this embodiment does not limit it here. Take the i-th cycle of a single-phase current data as an example, and analyze the possible jitter characteristics.

[0040] Taking any type of single-phase electrical parameters as an example, all the single-phase electrical parameters of any type in each cycle are combined into a single-phase electrical parameter sequence. This embodiment takes the i-th cycle of any single-phase current as an example for analysis, and arranges all current data of any single-phase current in the i-th cycle in ascending time order to obtain the single-phase current sequence of the i-th cycle. If a single-phase grounding fault occurs, the single-phase current sequence in the i-th cycle exhibits a fast jitter feature, so that it contains more high-frequency signals, while in a normal state, the single-phase current sequence is mainly a low-frequency signal.

[0041] It should be noted that the single-phase current sequence and the single-phase voltage sequence are both recorded as single-phase electrical parameter sequences.

[0042] Therefore, this embodiment constructs the Hankel matrix of the single-phase current sequence of the i-th cycle, and uses the singular value decomposition (SVD) algorithm to obtain all singular values ​​of the Hankel matrix, and arranges these singular values ​​in order from large to small to form a singular value sequence. The construction of the Hankel matrix and the SVD algorithm are both existing well-known technologies, and the specific process will not be repeated. Since the larger singular value represents the part with concentrated energy in the single-phase current sequence, it is usually related to the low-frequency signal, and the smaller singular value represents the part with less energy in the single-phase current sequence, which is usually related to the high-frequency component. Therefore, if the previous singular value in the singular value sequence is larger, it indicates that the single-phase current sequence is more likely to belong to a low-frequency signal, and if the previous singular value is smaller, the single-phase current sequence is more likely to belong to a high-frequency signal.

[0043] For the singular value sequence corresponding to the i-th period, the cumulative sum of the differences between each singular value and all remaining singular values ​​is calculated, and the average of the cumulative sum of all singular values ​​in the singular value sequence is used as the jitter coefficient of the single-phase current sequence of each period. The larger the jitter coefficient, the more obvious the rapid jitter characteristics of the single-phase current sequence of the i-th period.

[0044] It should be noted that the difference represents the degree of difference between two data, and can be calculated specifically by using the absolute value of the difference, the ratio, the sum of the squares of the differences, etc. This embodiment uses the ratio as the calculation method for the difference between the singular values ​​and all the remaining singular values.

[0045] S3, analyzing the correlation between the single-phase electrical parameter sequence of each period and its frequency component, as well as the distribution of the frequency component, to determine the fundamental frequency deviation coefficient of the single-phase electrical parameter sequence of each period; combining the jitter coefficient and the fundamental frequency deviation coefficient to determine the distortion coefficient of the single-phase electrical parameter sequence of each period; analyzing the difference between the distortion coefficient of each period and its adjacent periods to determine the proximity distinction of the single-phase electrical parameter sequence of each period.

[0046] In addition, the ground fault causes the single-phase current sequence to present a non-periodic characteristic, that is, the waveform change of the single-phase current sequence deviates from the standard sinusoidal waveform. This embodiment adopts a sliding window iterative DFT (Discrete Fourier Transform) algorithm to obtain the fundamental component and harmonic component of the single-phase current sequence. Under normal conditions, there are fewer harmonic components in the single-phase current sequence, mainly the fundamental component of the standard sinusoidal waveform. The sliding window iterative DFT (Discrete Fourier Transform) algorithm is an existing well-known technology, and this embodiment will not be described in detail here.

[0047] The discrete degree of the harmonic component of the single-phase electrical parameter sequence of each period is calculated, which is recorded as the first discreteness. The similarity between the single-phase electrical parameter sequence of each period and its fundamental component is calculated, and the ratio of the first discreteness to the similarity is used as the fundamental frequency deviation coefficient of the single-phase current sequence of each period. The larger the fundamental frequency deviation coefficient, the more significant the non-periodic characteristics of the single-phase current waveform in the period.

[0048] It should be noted that the specific calculation method of the degree of dispersion can be variance, standard deviation, coefficient of variation, etc. This embodiment uses standard deviation as the calculation method of the first dispersion. The specific calculation method of similarity can be cosine similarity, Pearson correlation coefficient, etc. This embodiment uses Pearson correlation coefficient as the calculation method of similarity.

[0049] Therefore, the distortion coefficient of the single-phase current sequence in the i-th cycle is calculated. The specific calculation method is:

[0050] ; In the formula, is the distortion coefficient of the single-phase current sequence in the ith cycle, is the jitter coefficient of the single-phase current sequence in the ith cycle, is the fundamental frequency deviation coefficient of the single-phase current sequence in the i-th cycle.

[0051] If the distortion coefficient of the i-th cycle is larger, it indicates that the distortion degree of the single-phase current data in the cycle is larger, and it is more likely to be caused by single-phase grounding.

[0052] Single-phase current distortion caused by ground fault usually only occurs in a short period of time, while the unstable characteristics of the data collected by the non-contact sensor caused by environmental changes are usually reflected in multiple cycles. By comparing the single-phase current waveform distortion characteristics and amplitude change characteristics between adjacent cycles, the negative impact of unstable data collected by non-contact sensors can be further avoided.

[0053] For any single-phase current, for the waveform distortion characteristics caused by the ground fault, the absolute values ​​of the differences between the distortion coefficients corresponding to the i-th cycle and the previous cycle and the next cycle are calculated respectively, recorded as the first absolute values ​​of the differences, and the average of the first absolute values ​​of the differences is used as the neighborhood distinction of the single-phase current sequence of the i-th cycle. The larger the neighborhood distinction, the more likely it is that the single-phase current in the i-th cycle is abnormal.

[0054] It should be noted that, for the distortion coefficient corresponding to the first cycle, the absolute value of the difference between it and the distortion coefficient corresponding to the next cycle is used as the proximity distinction of the single-phase current sequence of the first cycle. For the distortion coefficient corresponding to the last cycle, the absolute value of the difference between it and the distortion coefficient corresponding to the previous cycle is calculated as the proximity distinction of the single-phase current sequence of the last cycle.

[0055] S4, analyzing the difference in amplitude change between the single-phase electrical parameter sequence of each cycle and its adjacent cycles, and determining the peak distinctiveness of the single-phase electrical parameter sequence of each cycle; combining the adjacent distinctiveness with the peak distinctiveness, determining the difference coefficient of the single-phase electrical parameter sequence of each cycle; and taking the fusion result of the difference coefficient of any type of three-phase electrical parameters of each cycle as the local difference of any type of three-phase electrical parameters of each cycle.

[0056] For the amplitude change caused by ground fault, this embodiment adopts an automatic multiple-degree peak search algorithm to obtain the peak point of the single-phase current sequence in each cycle. When the transmission line is in a normal state, the number of peaks obtained in the single-phase current sequence is often small, but when a ground fault occurs, the number of peaks will increase significantly, and the abnormality of the amplitude is relatively large.

[0057] Therefore, in this embodiment, the absolute value of the difference between any peak value of the single-phase current sequence of the i-th cycle and each peak value of the single-phase current sequence of the previous cycle, as well as the absolute value of the difference with each peak value of the single-phase current sequence of the next cycle are calculated, and both are recorded as the second absolute value of the difference, and the sum of all the second absolute values ​​of the difference corresponding to any peak value of the single-phase current sequence of the i-th cycle is calculated, and the fusion result of the sum of all the peak values ​​of the single-phase current sequence of the i-th cycle is used as the peak distinction of the single-phase current sequence of the i-th cycle.

[0058] It should be noted that fusion means combining multiple values, which can be calculated by addition, multiplication, averaging, etc. In this embodiment, the average of the sum of all peak values ​​of the single-phase current sequence of the i-th cycle is used as the peak difference of the single-phase current sequence of the i-th cycle. The greater the peak difference, the greater the amplitude change of the single-phase current data in the cycle, and the greater the possibility of a fault.

[0059] It should be noted that, in the process of calculating the peak discrimination, the first cycle and the last cycle are obtained by using the same processing method as the distortion coefficient.

[0060] Thus, the difference coefficient of the single-phase current sequence of the i-th cycle is calculated. The specific calculation method is:

[0061] ; In the formula, is the difference coefficient of the single-phase current sequence in the i-th cycle, The neighboring distinction of the single-phase current sequence in the i-th cycle, The peak difference of the single-phase current sequence in the i-th cycle.

[0062] The larger the difference coefficient corresponding to the i-th cycle is, the more drastic the change of the single-phase current data in the cycle is, and the greater the possibility of a fault occurring is.

[0063] When a ground fault occurs in the transmission line, each single-phase current data of the three-phase current will show abnormality in the same cycle. The sum of the difference coefficients of the single-phase current sequences corresponding to all single-phase currents in the i-th cycle is taken as the local difference of the three-phase current in the i-th cycle.

[0064] S5, analyzing the discrete degrees of the local differences of various three-phase electrical parameters in all cycles to obtain the fault monitoring results of the transmission line.

[0065] The local differences of the three-phase currents of all cycles are arranged in ascending order of time to form an abnormal feature sequence of the three-phase current. When the transmission line is in a normal state, the obtained abnormal feature sequence remains relatively stable without obvious fluctuations despite the influence of the data collected by the non-contact sensor. However, a ground fault will cause some data in the abnormal feature sequence to jump. Therefore, this embodiment calculates the coefficient of variation of the abnormal feature sequence, which is recorded as the second discreteness. The larger the obtained coefficient of variation, the greater the degree of jump of the abnormal feature sequence, and the more likely a fault will occur.

[0066] In addition, for the collected three-phase voltage data, the same calculation method as the three-phase current data is used to obtain the second discreteness corresponding to the three-phase voltage data, and the product of the second discreteness corresponding to the three-phase current data and the second discreteness corresponding to the three-phase voltage data is used as the fault characteristic value of the transmission line. The flow chart of constructing the fault characteristic value of the transmission line is as follows: Figure 2 shown.

[0067] The larger the fault characteristic value obtained, the closer the fault characteristics of the three-phase current and the three-phase voltage are, and the greater the possibility of a ground fault in the transmission line.

[0068] This embodiment adopts the Sigmoid function to obtain the normalized result of the fault characteristic value of the transmission line. The implementer can select other existing feasible normalization methods according to the actual situation. This embodiment does not limit it here. A fault threshold is set. If the normalized result is greater than or equal to the fault threshold, it is determined that a ground fault has occurred in the transmission line. If the normalized result is less than the fault threshold, it is determined that the transmission line is normal.

[0069] In this embodiment, the fault threshold is manually set to 0.8, and the implementer can set it according to the actual situation, and this embodiment does not limit it.

[0070] Based on the same inventive concept as the above method, an embodiment of the present application also provides a non-contact power transmission line fault monitoring device, including a memory, a processor, and a computer program stored in the memory and running on the processor, and when the processor executes the computer program, the steps of any one of the above-mentioned non-contact power transmission line fault monitoring methods are implemented.

[0071] It should be noted that the above sequence of the embodiments of the present application is for description only and does not represent the advantages and disadvantages of the embodiments. The above is a description of a specific embodiment of this specification. In addition, 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.

[0072] 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.

[0073] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions, improvements, etc. made within the principles of the present application should be included in the protection scope of the present application.

Claims

1. A non-contact transmission line fault monitoring method, characterized in that: The method comprises the following steps: Collect various three-phase electrical parameters of the transmission line at all times; Divide any type of single-phase electrical parameters at all times into periods, form all the single-phase electrical parameters of any type in each period into single-phase electrical parameter sequences, obtain the Hankel matrix of each single-phase electrical parameter sequence, calculate the cumulative sum of the differences between each singular value corresponding to the Hankel matrix and all remaining singular values, and use the mean of all the cumulative sums of each single-phase electrical parameter sequence as the jitter coefficient of the single-phase electrical parameter sequence of each period; Calculate the degree of discreteness of the harmonic component of the single-phase electrical parameter sequence of each cycle, recorded as the first discreteness; calculate the similarity between the single-phase electrical parameter sequence of each cycle and its fundamental component, and use the difference between the first discreteness and the similarity as the fundamental frequency deviation coefficient of the single-phase electrical parameter sequence of each cycle; combine the jitter coefficient and the fundamental frequency deviation coefficient to determine the distortion coefficient of the single-phase electrical parameter sequence of each cycle; analyze the difference between the distortion coefficient of each cycle and its adjacent cycles, and determine the adjacent distinction of the single-phase electrical parameter sequence of each cycle; Acquire each peak value of the single-phase electrical parameter sequence of each cycle, calculate the sum of the differences between the peak values ​​of each cycle and the peak values ​​of the adjacent cycles, and use the fusion result of all the sum values ​​of each cycle as the peak difference of the single-phase electrical parameter sequence of each cycle; combine the adjacent difference with the peak difference to determine the difference coefficient of the single-phase electrical parameter sequence of each cycle; use the fusion result of the difference coefficient of any type of three-phase electrical parameters of each cycle as the local difference of any type of three-phase electrical parameters of each cycle; The discrete degrees of the local differences of various three-phase electrical parameters in all cycles are analyzed to obtain the fault characteristic values ​​of the transmission line and the fault monitoring results of the transmission line.

2. A non-contact power transmission line fault monitoring method as claimed in claim 1, characterized in that: The distortion coefficient is the product of the jitter coefficient and the fundamental frequency deviation coefficient.

3. A non-contact power transmission line fault monitoring method as claimed in claim 1, characterized in that: The neighboring distinction is the average of the differences between the distortion coefficients of each period and its neighboring periods.

4. A non-contact power transmission line fault monitoring method as claimed in claim 1, characterized in that: The difference coefficient is the product of the proximity distinction and the peak distinction.

5. A non-contact power transmission line fault monitoring method as claimed in claim 1, characterized in that: The obtaining of the fault monitoring result of the transmission line comprises: The discrete degree of the local difference of various types of three-phase electrical parameters of all cycles is recorded as a second discreteness, and the fusion result of the second discreteness of all types of three-phase electrical parameters is used as a fault characteristic value of the transmission line; A fault monitoring result of the transmission line is obtained based on the fault characteristic value.

6. A non-contact power transmission line fault monitoring method as claimed in claim 5, characterized in that: If the normalized value of the fault characteristic value is greater than or equal to a preset fault threshold, it is determined that a ground fault occurs in the transmission line; otherwise, it is determined that the transmission line is normal.

7. A non-contact power transmission line fault monitoring device, comprising a memory, a processor, and a computer program stored in the memory and running on the processor, characterized in that: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 6 are implemented.

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