Corona field delay type lightning rod and operation monitoring method

Abstract

The invention relates to the technical field of lightning rod lightning protection monitoring, in particular to a corona field delay type lightning rod and an operation monitoring method, and the method comprises the steps: collecting corona current and electric field intensity at each moment in each monitoring period in the operation process of the lightning rod; calculating a first evaluation value and an electric field anomaly degree of each time period in each monitoring period to obtain a first interference degree of each time period in each monitoring period; determining a second evaluation value and a period abnormity degree of each time period in each monitoring period, and obtaining a second interference degree of each time period in each monitoring period; and determining the interference coefficient of each monitoring period, and evaluating the monitored data distortion condition during the operation of the lightning rod. The monitored data distortion condition is evaluated, so that the possibility of misjudgment or missed judgment of the lightning stroke risk by the lightning rod is reduced, and the strength of corona discharge generated by the corona field delay type lightning rod under the action of an electric field and the thundercloud activity evaluation precision are improved.

Description

Technical Field

[0001] The present application relates to the technical field of lightning rod lightning protection monitoring, and in particular to a corona field delay type lightning rod and an operation monitoring method. Background Art

[0002] As an active lightning protection device, the corona field delay type lightning rod interferes with the lightning development process through the ion layer formed by corona discharge, expanding the protection range and reducing the risk of lightning strikes. Its core is to use the release of corona ions to inhibit the triggering of the upward leader or delay or prevent the establishment of the lightning channel. The purpose of monitoring the operation of the corona field delay type lightning rod is to accurately understand the corona ion release status, electric field response status, and equipment operating status of the lightning rod. This provides effective data support for technical improvements such as preventing lightning accidents caused by protection failure, extending equipment service life, and optimizing lightning protection strategies.

[0003] Traditional lightning rod operation monitoring technology still has certain drawbacks. For example, when the wind speed is too high, the corona ion layer formed by the corona discharge of the lightning rod will be blown away, destroying the stability of the corona ion layer and causing local electric field distortion. Secondly, excessively high ambient humidity will cause a conductive water film to form on the surface of the lightning rod, increasing the surface leakage current, thereby masking the true corona current, causing the monitoring data of the corona field delay type lightning rod to be distorted, unable to accurately reflect the actual operating status of the lightning rod, and increasing the possibility of misjudgment or omission of lightning strike risks. Summary of the Invention

[0004] In order to solve the above technical problems, a corona field delay type lightning rod and an operation monitoring method are provided to solve the existing problems.

[0005] The solution to the technical problem of this application is to provide a corona field delay type lightning rod and an operation monitoring method, comprising the following steps: In a first aspect, an embodiment of the present application provides a method for monitoring the operation of a corona field delay type lightning rod, the method comprising the following steps: Collect the corona current and electric field strength at each moment in each monitoring cycle during the operation of the lightning rod; and divide all moments in each monitoring cycle into multiple time periods; Perform frequency domain analysis on all corona currents in each time period to obtain a spectrum diagram and power spectrum; analyze the proportion of the power spectrum density of the high-frequency frequency components in the power spectrum, as well as the extreme changes in the corona current, and calculate the first evaluation value for each time period in each monitoring cycle; Analyze the abnormality of the synchronous change of the electric field intensity and the corona current at different times in each time period, as well as the discreteness of the electric field intensity, calculate the electric field abnormality of each time period in each monitoring cycle, and combine the first evaluation value to obtain the first interference degree of each time period in each monitoring cycle; The second evaluation value of each time period in each monitoring cycle is determined by the difference changes in the peaks and troughs of the corona current at all times in each time period and the energy dispersion of the low-frequency frequency components in the spectrum diagram; According to the difference in the time interval between the peak and the trough of the corona current at all times in each time period and the periodicity of the corona current, the periodic abnormality of each time period in each monitoring cycle is calculated, and combined with the second evaluation value, the second interference degree of each time period in each monitoring cycle is obtained; Based on the first interference degree and the second interference degree in all time periods, the interference coefficient of each monitoring cycle is determined, and the distortion status of the data monitored during the operation of the lightning rod is evaluated.

[0006] Preferably, the calculating of the first evaluation value for each time period in each monitoring cycle includes: The frequency components in the frequency spectrum and the power spectrum that are greater than the preset frequency are recorded as high-frequency components, and vice versa as low-frequency components; The ratio of the sum of the power spectrum densities of all high-frequency components in the power spectrum to the sum of the power spectrum densities of all frequency components is recorded as the high-frequency ratio; Calculate the product of the range and mean of the corona current at all times in each period of each monitoring cycle, and record it as the fluctuation; The first evaluation value is the product of the volatility and the high frequency ratio.

[0007] Preferably, the calculation of the electric field anomaly degree in each time period in each monitoring cycle includes: The ratio of the electric field intensity to the corona current at each moment is recorded as the instantaneous field-current ratio; a curve fitting is performed on the instantaneous field-current ratio at all moments in each period of each monitoring cycle, and the curvature of the fitting curve at each moment is calculated; Calculate the product of the mean and variance of the curvature at all moments in each period, and record it as the nonlinear intensity; Calculate the dispersion degree of the electric field intensity at all times in each time period, and record it as the first dispersion degree; The electric field anomaly degree is the product of the nonlinear intensity and the first discreteness.

[0008] Preferably, the first interference degree is the product of the first evaluation value and the electric field anomaly degree.

[0009] Preferably, determining the second evaluation value for each time period in each monitoring cycle includes: Calculating the discrete degree of energy of all low-frequency components in the spectrum graph, which is recorded as a second discrete degree; Obtain the peaks and troughs of the corona current at all times in each period of each monitoring cycle; Calculate the time interval between the corresponding moment of each peak and the corresponding moment of the trough, and select the trough with the smallest time interval from each peak, which is recorded as the adjacent trough; Calculate the difference between the peak value of each wave crest and the valley value of its adjacent valley, and record it as the reference value of each wave crest; Calculate the cumulative sum of the differences between the reference values of any two adjacent peaks in each time period of each monitoring cycle; The second evaluation value is a product of a result of performing forward mapping on the accumulated sum and the second discreteness.

[0010] Preferably, the calculation of the period anomaly degree of each time period in each monitoring cycle includes: For each monitoring period, the autocorrelation coefficients of multiple lag orders of the corona current at all times in each period are calculated; the mean of the autocorrelation coefficients corresponding to all lag orders in each period is calculated and recorded as the correlation degree; The time between the corresponding moment of each peak and the corresponding moment of its adjacent trough is recorded as the half-width; Calculate the sum of the differences in half-width between any two adjacent peaks in each time period; The period anomaly degree is the product of the result of positive mapping of the sum value and the correlation degree.

[0011] Preferably, the second interference degree is the product of the period abnormality degree and the second evaluation value.

[0012] Preferably, the interference coefficient is a normalized result of the average value of the product of the first interference degree and the second interference degree in all time periods in each monitoring cycle.

[0013] Preferably, the evaluation of the distortion of the data monitored during the operation of the lightning rod includes: if the interference coefficient is less than a preset threshold, the data monitored by the lightning rod during the monitoring period is not distorted; otherwise, the data monitored by the lightning rod is distorted.

[0014] Secondly, the embodiments of the present application further provide a corona field delay type lightning rod, which includes a flash lightning rod 101, a corona needle 102, a side needle 103, a strong ionization discharge unit 104, a base 105, an inductive resonator 106, and an online ground resistance monitor 107.

[0015] This application has at least the following beneficial effects: The present application performs frequency domain analysis on the corona current, and calculates the first evaluation value of each time period in each monitoring cycle according to the proportion of high-frequency components in the power spectrum and the extreme changes of the corona current. The beneficial effect is that it takes into account the obvious high-frequency oscillation characteristics of the corona current, indicating that the corona ion layer generated by the corona field delay type lightning rod is destroyed, so as to reflect the possibility of imbalance of the corona ion layer and the instability of the corona current, so as to preliminarily evaluate the interference of the lightning rod with the ambient wind speed; secondly, the electric field anomaly degree of each time period in each monitoring cycle is calculated through the abnormal situation of the synchronous change of the electric field intensity and the corona current, and the discrete distribution of the electric field intensity. The beneficial effect is that it takes into account the complexity of the change of the electric field intensity. and abnormality to illustrate the degree of electric field distortion, and then further evaluate the interference of the ambient wind speed on the lightning rod through the imbalance degree of the synchronous change between the corona current and the electric field strength; obtain the first interference degree of each time period in each monitoring cycle, which has the beneficial effect of comprehensively evaluating the degree of damage to the corona ion layer of the corona field delay type lightning rod caused by wind field disturbance and the possibility of imbalance of the corona ion layer; calculate the second evaluation value of each time period in each monitoring cycle through the uneven energy distribution of the low-frequency component in the corona current and the difference in the baseline level of the corona current, which has the beneficial effect of taking into account the energy complexity of the frequency component of the corona current and the severe situation of the baseline drift of the corona current, so as to illustrate The significance of the superposition of different leakage currents caused by the water film formed on the surface of the lightning rod due to the influence of humidity is used to preliminarily evaluate the influence of environmental humidity on the corona current of the lightning rod; according to the periodic changes of the corona current and the changes in the pulse half-width of the pulse waveform, the periodic anomaly of each time period in each monitoring cycle is calculated. Its beneficial effect is that it takes into account the situation that the pulse waveform of the corona current is smoothed by the leakage current and the intensity of the periodic changes of the corona current, so as to further reflect the situation that the pulse waveform of the corona current is smoothed by the leakage current due to the influence of environmental humidity on the surface of the lightning rod, so as to evaluate the interference of environmental humidity on the surface of the lightning rod; determine the second interference degree of each time period in each monitoring cycle, and its beneficial effect is The method comprehensively measures the degree of obvious conductive water film formed on the surface of the lightning rod due to interference from environmental humidity; determines the interference coefficient of each monitoring cycle, and evaluates the distortion of the data monitored during the operation of the lightning rod. Its beneficial effect is that it can accurately reflect the degree to which the corona current ion layer generated by the corona field delay type lightning rod is destroyed by wind speed and the superimposed influence of leakage current caused by environmental humidity, and then evaluate the distortion of the data monitored by the corona field delay type lightning rod, thereby reducing the possibility of misjudgment or omission of lightning strike risk by the lightning rod, improving the accuracy of evaluating the strength of corona discharge generated by the corona field delay type lightning rod under the action of the electric field and thundercloud activity, and improving its accuracy and reliability in lightning protection. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The following is a further detailed description of a corona field delay type lightning rod operation monitoring method of the present application in conjunction with the accompanying drawings.

[0017] Figure 1 A flowchart of the steps of a corona field delay type lightning rod operation monitoring method provided in an embodiment of the present application; Figure 2 A flowchart of the steps of the method for obtaining the interference coefficient provided in an embodiment of the present application; Figure 3 This is a schematic structural diagram of the corona field delay type lightning rod provided in an embodiment of the present application. DETAILED DESCRIPTION

[0018] In order to make the purpose, technical solutions and advantages of this application more clearly understood, the following, in conjunction with the accompanying drawings and implementation examples, further describes in detail a corona field delay type lightning rod and operation monitoring method proposed in this application. It should be understood that the specific embodiments described herein are only used to explain this application and are not intended to limit this application.

[0019] 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.

[0020] See also Figure 1 , which shows a flowchart of a method for monitoring the operation of a corona field delay type lightning rod provided by an embodiment of the present application, the method comprising the following steps: Step 1: Collect the corona current and electric field strength at each moment in each monitoring cycle during the operation of the lightning rod.

[0021] Lightning protection devices ensure the stable operation of power equipment, and lightning arresters effectively protect the power grid from abnormal overvoltage conditions. Lightning activity in power systems can trigger overvoltages, damaging substation equipment, transmission lines, and terminal equipment. Lightning rods guide lightning through discharge at their tips, discharging the overvoltage along a predetermined path to the ground, preventing damage to equipment and ensuring the stability and reliability of the power system.

[0022] Secondly, corona field delay lightning rods suppress or delay the upward leader of a lightning strike through the corona ion layer. The upward leader is a discharge channel that extends from the ground or a protruding object, i.e., the lightning rod, toward the thundercloud. When a thundercloud approaches the ground, it causes electric field distortion on the surface of sharp objects on the ground. When the electric field intensity is large enough to reach the breakdown threshold of the air, these sharp objects, i.e., the lightning rods, will emit electrons upward, forming an upward leader. The accuracy of a lightning rod's ability to suppress or delay the upward leader of a lightning strike directly depends on the accuracy of the corona current and the electric field intensity at the tip of the lightning rod. However, the data collection process is significantly affected by environmental interference. If the data is distorted due to environmental interference such as wind speed and humidity, the lightning rod's suppression effect will fail, leading to misjudgment of its working status, resulting in the inability to accurately identify potential lightning strike risks and affecting the stability of the power system.

[0023] Based on the above analysis, a high-precision corona current sensor and a dual-probe electric field sensor are used to collect the corona current, electric field strength at the tip of the corona field delay type lightning rod, and the humidity of the surrounding environment in real time during its operation. The collected data are normalized and missing values are filled. Multiple moments are recorded as a monitoring cycle. In this way, the corona current, electric field strength, and ambient humidity at each moment in each monitoring cycle during the operation of the corona field delay type lightning rod are obtained. In this embodiment, the data acquisition frequency of the corona current sensor and the dual-probe electric field sensor is 100kHz, and the duration of each monitoring cycle is 1 minute. As other implementation methods, the implementer can set them according to actual conditions; secondly, Z-Score standardization is used for normalization processing, and the median filling method is used for missing value filling. Among them, Z-Score standardization and median filling method are well-known technologies and will not be repeated here.

[0024] At this point, the corona current and electric field strength at each moment in each monitoring cycle during the operation of the corona field delay type lightning rod are obtained.

[0025] Step 2: Perform frequency domain analysis on all corona currents in each time period to obtain a spectrum diagram and a power spectrum; analyze the proportion of the power spectrum density of the high-frequency frequency components in the power spectrum, and the extreme changes in the corona current, and calculate the first evaluation value of each time period in each monitoring cycle; analyze the abnormal situation of the synchronous change of the electric field intensity and the corona current at different times in each time period, and the discrete situation of the electric field intensity, calculate the electric field anomaly degree of each time period in each monitoring cycle, and combine the first evaluation value to obtain the first interference degree of each time period in each monitoring cycle.

[0026] During the operation of a corona field-delayed lightning rod, the corona current directly reflects the strength of the corona discharge generated by the lightning rod under the influence of the thundercloud's electric field. The release of corona ions inhibits or delays the triggering of the upward leader of lightning, reducing the risk of lightning channel establishment, thereby preventing the risk of lightning strikes. However, thundercloud electric fields are often accompanied by adverse meteorological factors. For example, ambient wind speed can cause an imbalance in the corona ion layer and cause electric field distortion, resulting in misjudgments or omissions in the monitoring of the operation of corona field-delayed lightning rods.

[0027] Among them, the greater the interference from the ambient wind speed, the higher the degree of damage to the corona ion layer, which increases the volatility of the corona current, weakens the corona discharge intensity as the ion density decreases, and the average level of the corona current is higher; and due to the electric field distortion and instability of the spatial charge distribution caused by the dissipation area of the corona ion layer, the random local discharge pulses increase, causing the corona current to show obvious high-frequency oscillation characteristics; at the same time, the electric field strength and the corona current show a positive correlation under the influence of ionization efficiency and dynamic balance of spatial charge, and the wind field disturbance makes the time synchronization correlation between the corona current and the electric field strength worse, and the abnormal fluctuation of the electric field strength is more obvious.

[0028] Based on the above analysis, the first interference degree is calculated through the abnormal changes of the corona current and the electric field strength, which is used to characterize the abnormal changes of the corona current and the electric field strength caused by the influence of wind speed.

[0029] First, analyze the fluctuation of corona current and high-frequency oscillation characteristics, and calculate the first evaluation value, specifically: Divide all moments in each monitoring cycle into multiple time periods; In this embodiment, the duration of each time period is 1 ms. For other implementations, the implementer may set the duration according to actual conditions.

[0030] Perform frequency domain analysis on the corona current at all times in each period of each monitoring cycle to obtain the spectrum and power spectrum; In this embodiment, fast Fourier transform is used to obtain the spectrum diagram and power spectrum, wherein fast Fourier transform is a well-known technology and will not be described here in detail. As other implementation methods, the implementer can adopt other methods of the existing technology, such as Hilbert-Huang transform, etc. This embodiment does not impose any special restrictions on this.

[0031] The frequency components in the frequency spectrum and the power spectrum that are greater than the preset frequency are recorded as high-frequency components, and vice versa as low-frequency components; In this embodiment, the preset frequency is 10kHz, and the frequency components in the frequency range of 10kHz to 40kHz are recorded as high-frequency components, and the frequency components less than 10kHz in the power spectrum are recorded as low-frequency components. As other implementation methods, the implementer can set them according to actual conditions.

[0032] The ratio of the sum of the power spectrum densities of all high-frequency components in the power spectrum to the sum of the power spectrum densities of all frequency components is recorded as the high-frequency ratio; It should be noted that the acquisition of power spectrum density is a well-known technology and will not be described in detail here.

[0033] Calculate the product of the range and mean of the corona current at all times in each period of each monitoring cycle, and record it as the fluctuation; The product of the volatility and the high-frequency ratio is used as the first evaluation value of each time period in each monitoring cycle; It should be noted that, the greater the high-frequency proportion, the more obvious high-frequency oscillation characteristics of the corona current are; the greater the fluctuation degree, the more violent the fluctuation of the corona current and the relatively greater the intensity of the corona discharge; the larger the obtained first evaluation value, the higher the degree of damage to the corona ion layer of the lightning rod, the greater the possibility of imbalance in the corona ion layer, and the more prominent the instability of the corona current.

[0034] Secondly, analyze the abnormality of the synchronous changes of electric field intensity and corona current, as well as the fluctuation of electric field intensity, and calculate the degree of electric field anomaly, specifically: The ratio of the electric field intensity to the corona current at each moment in each period of each monitoring cycle is recorded as the instantaneous field-current ratio; Perform curve fitting on the instantaneous field flow ratio at all moments in each time period and calculate the curvature of the fitting curve at each moment; In this embodiment, the least square method is used for curve fitting. The least square method and the calculation of curvature are both well-known technologies and will not be described in detail here.

[0035] Calculate the dispersion degree of the electric field intensity at all times in each time period in each monitoring cycle, and record it as the first dispersion degree; In this embodiment, the degree of dispersion is measured by calculating the approximate entropy of the electric field strength at all times in each time period in each monitoring cycle, wherein the approximate entropy calculation process is a well-known technology and will not be described in detail here.

[0036] Calculate the product of the mean and variance of the curvature at all moments in each period, and record it as the nonlinear intensity; The product of the nonlinear strength and the first discreteness is used as the electric field anomaly degree of each time period in each monitoring cycle; It should be noted that the larger the first discreteness is, the more complex and abnormal the change in electric field strength is, and the more interference factors may be involved, which may cause the electric field to be distorted; the larger the nonlinear intensity is, the more unstable the change in the ratio between the corona current and the electric field strength is, and the more significant the imbalance in the synchronous change between the corona current and the electric field strength is, and the greater the resulting electric field anomaly is, the more serious the impact of wind field disturbances is, and the higher the degree of damage to the corona ion layer of the lightning rod is.

[0037] Further, based on the first evaluation value and the electric field abnormality, a first interference degree is calculated, specifically: The product of the first evaluation value and the electric field abnormality is used as the first interference degree in each time period of each monitoring cycle; It should be noted that, the greater the first interference degree is, the more significantly the corona ion layer of the corona field delay type lightning rod is damaged by wind field disturbance, and the greater the possibility of the corona ion layer being unbalanced is.

[0038] Thus, the first interference degree of each time period in each monitoring cycle is obtained.

[0039] Step 3, by the difference variation of crest and trough in the corona current at all times in each period, and the energy discrete situation of the frequency component of low frequency in the spectrogram, determines the second assessed value of each period in each monitoring cycle; According to the difference variation of the time interval between crest and trough in the corona current at all times in each period, and the periodic correlation of corona current, calculate the cycle anomaly degree of each period in each monitoring cycle, in conjunction with the second assessed value, obtain the second interference degree of each period in each monitoring cycle.

[0040] During the operation of the corona field delayed lightning rod, there are still certain defects in evaluating the operating status of the lightning rod based solely on the first interference degree. The interference caused by the environmental humidity factor in the thundercloud electric field is not taken into account. If the interference from the environmental humidity is greater, a conductive water film will be formed on the surface of the lightning rod, and the water film will form a low-impedance channel, increasing the surface leakage current. This leakage current is highly coupled with the corona current generated by the lightning rod in the time domain, causing the real corona current to be masked.

[0041] Among them, when the interference from ambient humidity is greater, the more severe the formation of a conductive water film on the surface of the lightning rod, the more serious the situation of the uneven water film causing the corona current to form different leakage current paths on the surface of the lightning rod, the more complex the frequency components of the corona current, the greater the difference between the different low-frequency components formed by the obstruction and confinement of charged ions in the water film by water molecules, and the more severe the phenomenon of the baseline level of the corona current being increased by the superposition of leakage current. At the same time, the more severe the smoothing of the corona current pulse waveform by the leakage current, the more obvious the periodic changes of the corona current, and the more significant the increase in the half-width of the corona current pulse waveform. Therefore, the second interference degree is calculated to characterize the leakage current superposition caused by the water film on the surface of the lightning rod and the smoothing of the corona current waveform.

[0042] First, analyze the changes in the low-frequency components of the corona current and the distribution of different peaks in the corona current, and calculate the second evaluation value, specifically: Obtain the peaks and troughs of the corona current at all times in each period of each monitoring cycle; In this embodiment, the AMPD (Automatic Multiscale-based Peak Detection) algorithm is used to obtain peaks and troughs. The AMPD algorithm is a well-known technology and will not be described in detail here.

[0043] Calculate the time interval between the corresponding moment of each peak and the corresponding moment of the trough, and select the trough with the smallest time interval from each peak, which is recorded as the adjacent trough; The time between the corresponding moment of each peak and the corresponding moment of its adjacent trough is recorded as the half-width; Calculate the difference between the peak value of each wave crest and the valley value of its adjacent valley, and record it as the reference value of each wave crest; Calculate the cumulative sum of the differences between the reference values of any two adjacent peaks in each time period of each monitoring cycle; In this embodiment, the cumulative sum of the absolute values of the differences between the reference values of all any two adjacent peaks in each time period in each monitoring cycle is calculated.

[0044] Calculating the discrete degree of energy of all low-frequency components in the spectrum graph, which is recorded as a second discrete degree; In this embodiment, the degree of dispersion is measured by calculating the variance of the energy of all low-frequency components in the spectrum. As other implementation methods, the implementer may adopt other methods of the prior art, such as standard deviation, etc. This embodiment does not impose any special restrictions on this.

[0045] Performing positive mapping on the accumulated sum, and multiplying a result of the positive mapping by the second dispersion as a second evaluation value for each time period in each monitoring cycle; In this embodiment, the specific process of positive mapping is: positive mapping is performed through an exponential function, assuming that the cumulative sum is recorded as ,Will The result is the result of the positive mapping, where is an exponential function with a natural constant as its base.

[0046] It should be noted that the larger the second discreteness is, the more uneven the energy distribution of the low-frequency component is, the more complex the frequency component of the corona current is, and the more significant the unevenness of the leakage current path caused by the influence of environmental humidity is; the larger the result of the positive mapping is, the more drastic the baseline drift of the corona current is, and the more serious the influence of the superposition of leakage current is. Through the positive mapping, the cumulative effect of this change is further amplified. The larger the second evaluation value is, the more discrete the energy distribution of the low-frequency component caused by the interference of environmental humidity of the lightning rod corona current is, and the more drastic the change in the baseline level of the corona current is, reflecting that the superposition of different leakage currents formed on the surface of the lightning rod is more serious.

[0047] Secondly, analyze the periodic variation characteristics of the corona current and the interval between pulses, and calculate the periodic abnormality, specifically: Calculate the autocorrelation coefficients of multiple lag orders of the corona current at all moments in each time period in each monitoring cycle; In this embodiment, the autocorrelation coefficients corresponding to the corona currents at all moments in each time period in each monitoring cycle at lag orders of 10 to 30 are calculated. As other implementation methods, the implementers can set them according to actual conditions. It should be noted that the calculation of the autocorrelation coefficient is a well-known technology and will not be repeated here.

[0048] Calculate the mean of the autocorrelation coefficients corresponding to all lag orders and record it as the correlation; Calculate the sum of the differences in the half-width between any two adjacent peaks in each time period of each monitoring cycle, perform positive mapping on the sum, and multiply the result of the positive mapping by the correlation as the period anomaly degree of each time period in each monitoring cycle; In this embodiment, the specific process of positive mapping is: positive mapping is performed through an exponential function, assuming that the sum value is recorded as ,Will The result is the result of positive mapping of the sum value, where is an exponential function with a natural constant as its base.

[0049] It should be noted that, the greater the correlation, the higher the humidity, the leakage current will smooth the pulse waveform of the corona current, and the periodic change of the corona current will be more obvious, reflecting the change in the temporal correlation of the corona current and the influence of humidity on the periodicity of the corona current waveform; the greater the sum value, the leakage current caused by humidity will increase the half-width of the pulse of the corona current pulse waveform, and the difference in the half-width of different peaks will change significantly; the greater the periodic anomaly, the greater the influence of humidity interference, and the more serious the situation in which the pulse waveform of the corona current is smoothed by the leakage current.

[0050] Further, based on the period abnormality and the second evaluation value, a second interference degree is calculated, specifically: The product of the period abnormality and the second evaluation value is used as the second interference degree of each time period in each monitoring cycle; It should be noted that the greater the second interference degree, the more serious the leakage current superposition caused by the ambient humidity interference on the lightning rod and the more serious the abnormality of the corona current waveform, and the more obvious the conductive water film formed on the surface of the lightning rod.

[0051] Thus, the second interference degree of each time period in each monitoring cycle is obtained.

[0052] Step 4: Based on the first interference degree and the second interference degree of all time periods, determine the interference coefficient of each monitoring period, and evaluate the distortion status of the data monitored during the operation of the lightning rod.

[0053] During the operation monitoring of corona field delayed lightning rods, the stronger the wind speed and the higher the humidity in the thundercloud meteorological environment, the greater the degree of damage to the corona current ion layer of the lightning rod by the wind speed, the more obvious the conductive water film on the surface of the lightning rod caused by the environmental humidity, the more serious the distortion or masking of the collected corona current and environmental electric field, the more serious the interference of the monitoring data by the meteorological factors of thundercloud activity, and the more likely it is to lead to misjudgment and omission of lightning strike risks.

[0054] Based on the above analysis, the interference coefficient is calculated based on the first interference degree and the second interference degree to reflect the interference status of the corona current generated by the lightning rod and the electric field strength in the surrounding area due to environmental meteorological factors. Specifically, it is: Normalizing the average of the product of the first interference degree and the second interference degree in all time periods in each monitoring cycle as the interference coefficient of each monitoring cycle; In this embodiment, the The calculation formula of the interference coefficient of a monitoring cycle is: in, For the The interference coefficient of a monitoring cycle, For the In the monitoring cycle The first interference degree of each period, For the In the monitoring cycle The second interference degree of the time period, For the The number of all time periods in a monitoring cycle, It is a normalization function. In this embodiment, the sigmoid function is used for normalization. The sigmoid function is a well-known technology and will not be described here. As other implementation methods, the implementer can adopt other methods of the existing technology, such as the softmax function, etc. This embodiment does not impose any special restrictions on this.

[0055] It should be noted that the larger the interference coefficient, the more severe the damage to the corona ion layer of the lightning rod and the more serious the generation of a conductive water film on the surface of the lightning rod during the operation monitoring of the corona field delay type lightning rod, the stronger the degree of interference of the wind speed and humidity in the thundercloud electric field environment with the monitoring of the operation status of the lightning rod, and the greater the interference to the collected data, which reflects the abnormal conditions of the corona current and the environmental electric field strength of the lightning rod caused by the influence of the environmental wind speed and humidity during the operation of the corona field delay type lightning rod. The flowchart of the steps of the method for obtaining the interference coefficient provided in the embodiment of the present application is as follows: Figure 2 shown.

[0056] Then, based on the interference coefficient, the data distortion of the operation monitoring is evaluated, specifically: If the interference coefficient is less than the preset threshold, the data monitored by the lightning rod is not distorted; otherwise, the data monitored by the lightning rod is distorted; In this embodiment, the preset threshold value is 0.7. As for other implementation methods, the implementer can set it according to actual conditions.

[0057] It should be noted that when the interference coefficient is less than the preset threshold, the corona ion layer of the corona field delay type lightning rod is slightly affected by the wind speed damage, and the environmental humidity makes the leakage current superposition generated by the conductive water film on the surface of the lightning rod blurred. The data reliability of the corona field delay type lightning rod monitoring in this monitoring period is relatively high; on the contrary, the monitoring data of the lightning rod is seriously distorted by the interference of the environmental wind speed and humidity, and the possibility of misjudgment or missed judgment in the operation monitoring process of the corona field delay type lightning rod is relatively high. The inhibitory or delaying effect of the corona field delay type lightning rod on the upward leader of the lightning strike is reduced. It is necessary to promptly correct the corona current and electric field strength caused by the interference of meteorological factors to provide effective data support for the protection of lightning accidents caused by time-limited protection and the optimization of lightning protection strategies.

[0058] Based on the same inventive concept as the above method, the embodiment of the present application further provides a corona field delay type lightning rod, the corona field delay type lightning rod comprising: The lightning rod is responsible for delaying the corona field. When the corona ions generated by the lightning rod in a short period of time cannot eliminate and suppress the generation and development of the upward leader, the lightning rod in the middle of the equipment will receive the lightning, allowing the lightning current to discharge into the ground through the main equipment; Corona needle, responsible for gathering the suspended high voltage to generate corona; Side needles, responsible for protection against bypass and side lightning strikes; The strong ionization discharge unit is responsible for generating a large number of corona ions under the electric field of the thundercloud, forming a corona ion shielding layer above the protected object, inhibiting the initiation of the upward leader, weakening the development speed and intensity of the downward leader, and blocking the conduction of the upper and lower channels; thus avoiding the direct lightning phenomenon within the protection range; The base is used for support and grounding. The discharge electrode tooth shape design increases the voltage and facilitates corona discharge and grounding drainage. Inductive resonator, dispersive waveguide resonant cavity design, the polarity converter of the waveguide resonant cavity converts the polarity of the earth charge and sends it to the cavity impedance converter, achieving a lower thundercloud electric field to induce a large number of corona ions; Online ground resistance monitor, with real-time ground resistance monitoring function, facilitates inspections by operation and maintenance personnel, grid monitoring, and drone patrols.

[0059] The structural diagram of the corona field delay type lightning rod provided in this embodiment is as follows Figure 3 As shown, 101 is a lightning rod, 102 is a corona needle, 103 is a side needle, 104 is a strong ionization discharge unit, 105 is a base, 106 is an inductive resonator, and 107 is an online ground resistance monitor.

[0060] It should be understood that although Figure 1 The steps in the flowchart are shown in sequence as indicated by the arrows, but these steps are not necessarily executed in the order indicated by the arrows. Unless otherwise specified in this document, there is no strict order restriction for the execution of these steps, and these steps can be executed in other orders. In addition, Figure 1 At least part of the steps may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily executed at the same time, but can be executed at different times. The execution order of these sub-steps or stages is not necessarily sequential, but can be executed in turn or alternately with other steps or at least part of the sub-steps or stages of other steps.

[0061] The technical features of the above embodiments can be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0062] The above-described embodiments merely represent several implementation methods of the present application. While the descriptions are relatively specific and detailed, they should not be construed as limiting the present application. It should be noted that a person skilled in the art can make various modifications and improvements without departing from the spirit of the present application. Therefore, any simple modifications, equivalent variations, and modifications to the above embodiments made in accordance with the technical essence of the present application without departing from the content of the present application's technical solution fall within the scope of protection of the present application's technical solution.

Claims

1. A method for monitoring the operation of a corona field delay type lightning rod, characterized in that: The method comprises the following steps: Collect the corona current and electric field strength at each moment in each monitoring cycle during the operation of the lightning rod; and divide all moments in each monitoring cycle into multiple time periods; Perform frequency domain analysis on all corona currents in each time period to obtain a spectrum diagram and power spectrum; analyze the proportion of the power spectrum density of the high-frequency frequency components in the power spectrum, as well as the extreme changes in the corona current, and calculate the first evaluation value for each time period in each monitoring cycle; Analyze the abnormality of the synchronous change of the electric field intensity and the corona current at different times in each time period, as well as the discreteness of the electric field intensity, calculate the electric field abnormality of each time period in each monitoring cycle, and combine the first evaluation value to obtain the first interference degree of each time period in each monitoring cycle; The second evaluation value of each time period in each monitoring cycle is determined by the difference changes in the peaks and troughs of the corona current at all times in each time period and the energy dispersion of the low-frequency frequency components in the spectrum diagram; According to the difference in the time interval between the peak and the trough of the corona current at all times in each time period and the periodicity of the corona current, the periodic abnormality of each time period in each monitoring cycle is calculated, and combined with the second evaluation value, the second interference degree of each time period in each monitoring cycle is obtained; Based on the first interference degree and the second interference degree in all time periods, the interference coefficient of each monitoring cycle is determined, and the distortion status of the data monitored during the operation of the lightning rod is evaluated.

2. A corona field delay type lightning rod operation monitoring method according to claim 1, characterized in that: The calculating of the first evaluation value for each time period in each monitoring cycle includes: The frequency components in the frequency spectrum and the power spectrum that are greater than the preset frequency are recorded as high-frequency components, and vice versa as low-frequency components; The ratio of the sum of the power spectrum densities of all high-frequency components in the power spectrum to the sum of the power spectrum densities of all frequency components is recorded as the high-frequency ratio; Calculate the product of the range and mean of the corona current at all times in each period of each monitoring cycle, and record it as the fluctuation; The first evaluation value is the product of the volatility and the high frequency ratio.

3. A corona field delay type lightning rod operation monitoring method according to claim 1, characterized in that: The calculation of the electric field anomaly degree in each time period in each monitoring cycle includes: The ratio of the electric field intensity to the corona current at each moment is recorded as the instantaneous field-current ratio; a curve fitting is performed on the instantaneous field-current ratio at all moments in each period of each monitoring cycle, and the curvature of the fitting curve at each moment is calculated; Calculate the product of the mean and variance of the curvature at all moments in each period, and record it as the nonlinear intensity; Calculate the dispersion degree of the electric field intensity at all times in each time period, and record it as the first dispersion degree; The electric field anomaly degree is the product of the nonlinear intensity and the first discreteness.

4. A corona field delay type lightning rod operation monitoring method according to claim 1, characterized in that: The first interference degree is a product of the first evaluation value and the electric field abnormality degree.

5. A corona field delay type lightning rod operation monitoring method according to claim 2, characterized in that: Determining the second evaluation value for each time period in each monitoring cycle includes: Calculating the discrete degree of energy of all low-frequency components in the spectrum graph, which is recorded as a second discrete degree; Obtain the peaks and troughs of the corona current at all times in each period of each monitoring cycle; Calculate the time interval between the corresponding moment of each peak and the corresponding moment of the trough, and select the trough with the smallest time interval from each peak, which is recorded as the adjacent trough; Calculate the difference between the peak value of each wave crest and the valley value of its adjacent valley, and record it as the reference value of each wave crest; Calculate the cumulative sum of the differences between the reference values of any two adjacent peaks in each time period of each monitoring cycle; The second evaluation value is a product of a result of performing forward mapping on the accumulated sum and the second discreteness.

6. A method for monitoring the operation of a corona field delay type lightning rod according to claim 5, characterized in that: The calculation of the period anomaly degree of each time period in each monitoring cycle includes: For each monitoring period, the autocorrelation coefficients of multiple lag orders of the corona current at all times in each period are calculated; the mean of the autocorrelation coefficients corresponding to all lag orders in each period is calculated and recorded as the correlation degree; The time between the corresponding moment of each peak and the corresponding moment of its adjacent trough is recorded as the half-width; Calculate the sum of the differences in half-width between any two adjacent peaks in each time period; The period anomaly degree is the product of the result of positive mapping of the sum value and the correlation degree.

7. A method for monitoring the operation of a corona field delay type lightning rod according to claim 1, characterized in that: The second interference degree is a product of the period abnormality degree and the second evaluation value.

8. A method for monitoring the operation of a corona field delay type lightning rod according to claim 1, characterized in that: The interference coefficient is a normalized result of the average value of the product of the first interference degree and the second interference degree in all time periods in each monitoring cycle.

9. A method for monitoring the operation of a corona field delay type lightning rod according to claim 1, characterized in that: The evaluation of the distortion of the data monitored during the operation of the lightning rod includes: if the interference coefficient is less than a preset threshold, the data monitored by the lightning rod in the monitoring period is not distorted; otherwise, the data monitored by the lightning rod is distorted.

10. A corona field delay type lightning rod, applied to the corona field delay type lightning rod operation monitoring method according to claim 1, characterized in that: The corona field delay type lightning rod comprises a lightning rod (101), a corona needle (102), a side needle (103), a strong ionization discharge unit (104), a base (105), an inductive resonator (106), and an online ground resistance monitor (107).

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