42 results about "Cloud to ground" patented technology

The invention relates to a digital lightning detection method and a device thereof. The method comprises the following steps: receiving an electromagnetic signal generated when cloud-to-ground flash lightning discharging to generate an electric detection signal; digitalizing the conditioned electric detection signal; filtering the digital signal; establishing a uniform time scale; establishing a lightning signal identification criterion and a digitized cloud-to-ground flash lightning signal identification model by a time determination method, a bipolar test method and a homopolar test method by considering transmission features of a lightning electromagnetic radiation waveform; establishing a time window preprocessing area, and acquiring a development trend of the input digital signal and the corresponding typical parameters; and computing and determining the parameters of the input digital signal in combination with data in the time window by the digitized cloud-to-ground flash lightning signal identification model . The device consists of an antenna, a signal conditioner, an analog to digital converter, a module of cloud-to-ground flash lightning signal identification model, a system control manager, an assistant control manager, a communication interface, an external memory and a clock.

The invention relates to a method for evaluating the lightning protection performance of a high-speed railway traction network. The method comprises the following steps of: dividing an evaluation area into a plurality of space grids by adopting a grid method, and counting a cloud-to-ground lightning density parameter and a lightning current probability density distribution parameter of each space grid within specific time based on massive lightning positioning system data by utilizing a computer by adopting a method for counting high-speed railway passage lightning parameters; establishing a calculation mode of calculating direct-lightning lightning strip-out rate, inductive thunder lightning strip-out rate and total lightning strip-out rate of each zone and the whole line of a high-speed railway within the specific time period by adopting a lightning strip-out rate calculation method; and taking the lightning strip-out rate of each zone as the basis, taking the whole-line lightning strip-out rate as the reference, acquiring thunder damage risk data information of each zone relative to the whole line within the specific time period, and realizing the lightning protection performance evaluation of the spatial and temporal difference of the high-speed railway traction network. According to the method, the calculated lightning strip-out rate is close to real conditions based on the massive perennial lightning positioning system observation data.

The invention relates to a lightning monitoring and early warning method and system. The method comprises the steps of S1, detecting atmosphere average electric fields, optical radiation signals, electric field changing signals, magnetic field changing signals and GPS satellite signals of an area to be monitored and conducting signal conditioning and conversion, S2, judging whether the electric field changing amount meets preset triggering conditions or not according to the electric field changing signals, conducting signal collection and storage and executing the step S3 if the electric field changing amount meets the preset triggering conditions, and refreshing and awaiting if the electric field changing amount does not meet the preset triggering conditions, S3, conducting waveform characteristic extraction on the collected optical radiation signals, the collected electric field changing signals and the collected magnetic field changing signals, conducting cloud-to-ground lightning identification and location according to extracted characteristic parameters, and meanwhile storing and displaying the position of lightning in a geographic information system, the lightning time and waveforms of the optical radiation signals, the electric field changing signals and the magnetic field changing signals in the lightning process, and S4, generating early warning results according to cloud-to-ground lightning identification and location results and atmosphere average electric field amplitudes, and giving an warning signal according to the early warning results.

The invention discloses a power transmission line tower lightning strike risk evaluation method based on the data mining technology. The power transmission line tower lightning strike risk evaluation method based on the data mining technology comprises the steps that the coordinates of a power transmission line tower, the structure information of the tower and insulating configuration information are input into a GIS, and the elevation information around the tower and the cloud-to-ground lightning density degree of the position where the tower is located are extracted by means of the GIS; topographic feature parameters are calculated according to the elevation information; calculation is conducted according to the coordinates of the tower, the structure of the tower and the insulating configuration information, so that a predicted value of the lightning strike trip-out rate of the tower is obtained. The power transmission line tower lightning strike risk evaluation method based on the data mining technology is characterized by further comprising the steps that the obtained topographic feature parameters of the tower, the obtained cloud-to-ground lightning density degree, the obtained predicted value of the lightning strike trip-out rate and obtained lightning strike trip records are input by means of data mining software, a data mining model is established, and the probability of lightning strike trips of the base tower is analyzed and output; the lightning strike trip probability of the tower is compared with the lightning strike trip probability of a tower to which lightning strike strips happen once, so that the lightning strike trip risk grade of the tower is evaluated, and reliable data support is provided for lightning protection design of a power transmission line and lightning protection differentiation transformation of the power transmission line.

The invention discloses a thunderstorm kernel identification and tracing method based on a hybrid clustering algorithm. The method specifically includes the following steps of utilizing deployed thunder and lightning monitoring points to conduct exploration and record cloud-to-ground lightning data, conducting preprocessing on the recorded cloud-to-ground lightning data and dividing the data intolightning data sets of each equal time interval; adopting a GPS clock synchronization technology and an algorithm of time differences of arrival for figuring out spatial positioning coordinates of lightning according to the time differences of arrival of changeable radiation pulses of an electric field generated by the lightning to each station; on the basis of thunder and lightning positioning data figured out by means of the procedures above, utilizing a DBSCAN algorithm and a KMEANS algorithm to figure out the relevance of the thunder and lightning positioning data among a thunderstorm kernel center-of-mass coordinate position, the lightning frequency and a thunderstorm kernel. An experimental result indicates that the method can accurately reflect the change tendency of thunder and lightning on thunderstorm days, and great effects of identifying the thunderstorm kernel and movably tracing a thunderstorm are achieved.

A three dimensional full-lightning detection positioning system based on very-low frequency / low frequency comprises a data processing center station (20) and a plurality of detection substations installed on different positions, wherein the detection substations access to a wide area network, and through which data are sent to the data processing center station (20). The data centre station (20), upon reception of detection data of each detection substation, obtains the three-dimensional position of a lightning radiation source through three-dimensional lightning positioning algorithm. The VLF / LF antenna acquisition module (4) of each substation acquires magnetic field, electric field and GPS time setting signals and transmits the magnetic field, the electric field and the GPS time setting signals to a channel processing module (5), the channel processing module (5) transmits the signals after processing to a lightning signal identifying module (6), and the lightning signal identifying module (6) determines whether the lighting is intracloud lightning or cloud-to-ground lightning according to the characteristics of the intracloud lightning and the cloud-to-ground lightning. A clock synchronization module (7) marks time labels on the lightning signals, and transits to a data emission module (8). The data emission module (8) sends the lightning data to the data processing center station (20).

The invention provides a thunder damage protection risk automatic assessment method for a power transmission line. The thunder damage protection risk automatic assessment method comprises the steps of collecting parameters of a typical pole tower and recording values of parameters comprising thunder parameters, pole tower parameters, landform parameters, line parameters and cloud-to-ground lightning parameters; establishing a back striking calculation model and a shielding failure calculation model according to the parameters of the typical pole tower; calculating the shielding failure trip-out rate n1 of the pole tower on the basis of electromagnetic transient calculation program and according to the parameters of the typical pole tower and the shielding failure calculation model; calculating the pole tower shielding failure trip-out rate n1=NgP1eta on the basis of a guiding developing model; calculating the average lightning stroke trip-out rate N according to the back striking trip-out rate n1 and the shielding failure trip-out rate n2; and performing grading on the whole line pole tower based on lightning stroke risks according to the average lightning stroke trip-out rate N. The pole tower with the severe anti-thunder situation can be found before lightning stroke faults occur in the line, modification measures are adopted ahead of time, and the lightning stroke trip-out rate of the power transmission line is reduced.

The invention relates to an all-in-view lightning event observation system and an all-in-view lightning event observation method. The system may comprise a shooting device, a tank body, a temperature control device, a light shading device, a control module, a power module, a sensor, a data acquisition device, a global positioning system (GPS) antenna, a GPS time service module and a processing unit, wherein the shooting device can shoot an all-in-view digital image and directly transmit the all-in-view digital image to the processing unit; and the processing unit continuously acquire corona current by the data acquisition device, judges whether an observed range has thunderstorms or not, starts the light shading device to enter a lightning channel image shooting mode if the observed rangehas the thunderstorms, and stops the light shading device after the observation is finished to protect the shooting device when the observed range does not have the thunderstorms. The system simultaneously records the GPS time of a lightning event and the waveform information of corona current change produced by the lightning event, judges a lightning type and the polarity of cloud-to-ground lightning, can realize the automatic light shading of the shooting device and automatic control over the working environment temperature of the shooting device in the thunderstorms, and also can work in afield environment stably and reliably for long.

Methods, systems, and computer program products are described herein for generating proxy reflectivity data associated with lightning activity. A computing device receives data associated with lightning activity for one or more geographical areas. The computing device determines the logarithmic scale of the combined in-cloud and cloud-to-ground flash rate (dBR) for one or more grids of lightning activity based on the received data. The computing device generates proxy reflectivity data based on the dBR of the grids.

The invention relates to a method for assimilating cloud-to-ground lightning data through physical initialization. The method comprises the following steps that (1), three-dimensional agent radar echoes converted through the lightning data are screened in the vertical direction to obtain the maximum echo reflectivity factor Ze; (2), precipitation intensity RR'obs is obtained according to a formula, and the precipitation intensity is converted into the precipitation flux mode RRobs; (3), the cloud top height is set to be the top height of the three-dimensional agent radar echoes, cloud bottom height is approximately substituted by the isentropic condensation level of a background field; (4), vertical ascending velocity in a cloud is expressed; (5), when the precipitation intensity RR'obs is smaller than the area of 0.1, the vertical velocity is kept consistent with that of the background, specific humidity and the cloud water content are not changed, the cloud water content is set to be zero, maximum relative humidity cannot exceed 80 percent, and when the precipitation intensity RR'obs is larger the area of 0.1, the specific humidity and the cloud water content are adjusted. The method can effectively improve nowcasting precision of a mode on a severe convection system.

The invention relates to a full lightning cloud cloud-to-ground lightning recognition method. The method can be used for recognizing different lightning types, includes intracloud discharging and cloud-to-ground discharging recognition and recognition of a special cloud lightning event (NBE) and can be used for conventional cloud-to-ground lightning and position cloud lightning. A specific waveform parameter extraction method is adopted to extract collected lightning field waveform parameters, the extracted lightning waveform parameters are utilized for comprehensive judgment, and lightning discharging types are given according to judgment results.

The invention relates to a lightning current parameter detection apparatus. The lightning current parameter detection apparatus includes measuring coils, a voltage adjusting module, a data acquisition card, an optical fiber module and a computer which are connected in series with one another sequentially; the measuring coil comprises a plurality of parallel coils with different measuring ranges; the coil comprises a linear frame; the linear frame is uniformly wound with enameled wires, so that a hollow sing-layer linear coil can be formed; the measuring coils are connected with the voltage adjusting module and the data acquisition card through a cable; and the data acquisition card transmits signals to the computer through using an optical fiber and by means of the optical fiber module. According to the lightning current parameter detection apparatus, lightning current can be positioned through using a time-difference method and by means of the plurality of measuring coils located at different positions, and therefore, cloud-to-ground lightning density of a small area can be determined, and the comprehensiveness of measurement can be improved.

The invention relates to a lightning warning method applicable to distribution networks, which includes any of the following sub methods or a combination of a plurality of sub methods. In a first sub method, lightning is detected using a multi-vector photo-magnetic complex-mode induction technology to get the type, direction and relative distance of lightning, and a warning is then issued according to the type, direction and relative distance. In a second sub method, a power grid is partitioned, and a warning is issued according to the connection relationship of the partitions. In a third sub method, the lightning warning level is adjusted according to the real-time operation state of a power grid. In a fourth sub method, whether it is intra-cloud lightning or cloud-to-ground lightning is detected and identified, and a warning is issued according to the result of detection and identification. In a fifth sub method, a warning is issued by integrating real-time lightning detection data and near-earth electric field detection data. Through one sub method or the combination of a plurality of sub methods, the power flow distribution condition, the real-time load condition and the lightning protection of equipment in a power grid are considered, and the accuracy of power grid lightning warning can be improved.

The invention discloses a method for judging a cloud-to-ground lightning high-risk section of a line corridor in combination with topographic parameters.The method comprises the steps of firstly, fitting the relation between a thunder and lightning day and the cloud-to-ground lightning density, conducting preliminary screening on lightning hazard risks of the line combination with the cloud-to-ground lightning density value and a line lightning stroke historical failure database, subsequently, conducting TPI analysis, combining the cloud-to-ground lightning density with topographic features, conducting further screening on the TPI threshold value, then calculating the back-striking, the shielding failure and total lightning trip-out rate, and finally according to a lightning trip-out rate control range, judging the cloud-to-ground lightning high-risk of the line corridor.By means of the method, organic combination of the cloud-to-ground lightning density, topographic position indexes and line lightning stroke historical data is achieved, the defect that the topographic features are not considered in traditional methods is made up, and the judgment result is more objective and scientific.

The invention provides a long-distance cloud-to-ground lightning single-station positioning method and a system thereof. The method comprises the steps of acquiring a lightning electromagnetic pulse through a magnetic field measurement sensor; determining a lightning signal through comparing the waveform of the lightning electromagnetic pulse with a standard lightning waveform; acquiring a determining time difference through detecting the lightning signal by multiple times, and finally determining a three-dimensional space parameter of a lightning generation position according to the determining time difference and an ionosphere height at a lightning signal acquiring time. According to the method of the invention, the azimuth and the height of the lightning generation position and a distance between the lightning generation position and a detecting station through the time difference between the time in directly arriving at the detecting station by the lightning electromagnetic pulse and the time in arriving at the detecting station by the lightning electromagnetic pulse after reflection by the ionosphere by multiple times. Positioning through a plurality of detecting stations is not required. Furthermore determining of the three-dimensional space parameter is performed through the time difference between the time in directly arriving at the detecting station and the time in arriving at the detecting station after reflection by the ionosphere for multiple times. The long-distance cloud-to-ground lightning single-station positioning method and the system thereof can greatlyprolong the detecting distance and furthermore settle problems of incapability of realizing single-station positioning and unsuitability for ultralong-distance positioning in a traditional lightning generation position positioning mode.

The invention relates to a method for converting the assimilated cloud-to-ground lightning of severe convection weather forecasting into proxy radar echoes. The method comprises: S1) obtaining the cloud-to-ground lightning data; S2) processing the cloud-to-ground lightning data and administering quality control thereto; S3) converting the cloud-to-ground lightning data into three-dimensional proxy echoes; and S4) substituting the proxy echoes to an assimilated three-dimensional variation system to realize the assimilation of the cloud-to-ground lightning data. The step 1 of obtaining the cloud-to-ground lightning data further comprises S11) selecting the time when the convection system starts to set the assimilation time; and S12) extracting the cloud-to-ground lightning data in the assimilation time period. According to the method for converting the assimilated cloud-to-ground lightning of severe convection weather forecasting into proxy radar echoes, the cloud-to-ground lightning data can be assimilated into a three-dimensional variation system, which increases the approaching forecasting for a severe convection system and makes the method applied to the currently available three-dimensional variation service system.

The invention relates to a calculation method for large-area region cloud-to-ground lightning density based on an improved grid method. The calculation method belongs to the technical field of power line design. The calculation method comprises the steps that a ground lightning database is created, and the database contains ground lightning time and geographical position information; the longitude range and latitude range of a selected region are divided into different grid cells according to selected accuracy, the left and right sides of the grid cell coincide with the longitude line, and the upper and lower sides of the grid cell coincide with the altitude line, the division accuracy is set to be p, the altitude of one side, close to the equator, of the upper and lower sides of the grid cell is lat, and the area of each grid cell is calculated; the annual ground lightning times of each grid cell is calculated according to the data statistics of the ground lightning database; the cloud-to-ground density of each grid cell is calculated according to the divided grid areas; the calculation result is displayed in a digital map. The calculation method can calculate the cloud-to-ground lightning density of regions with large latitude difference more accurately and provide an effective reference frame for the selection of lightning protection level in power line design and reconstruction.

An LLS-based regional lightning damage feature correlation analysis method is characterized in that the correlation between the spatial features of cloud-to-ground lightning and the meteorological background extracted from NECP reanalysis data is determined through singular value decomposition based on cloud-to-ground lightning monitoring data of a lightning location system and the NECP reanalysis data, and therefore, factors strongly correlated with the features of regional lightning damage can be analyzed and identified. The method of the invention has the characteristics of easy field application, high-reliability algorithm, and high reference value in auxiliary decision making. The method of the invention can be applied to a provincial power company power dispatching institution which has rich experience in running a lightning location system, provides accurate cloud-to-ground lightning analysis and is equipped with a grid meteorological information system in a power grid. A method for screening meteorological conditions affecting the features of regional lightning damage is provided, and the construction of the capability of the power grid to resist lightning damage is promoted.

The invention discloses a method for drawing a distribution map of lightning stroke tripping risk. The method comprises: obtaining power grid parameters and lightning stroke parameters of a to-be-analyzed region; dividing the to-be-analyzed region into a plurality of grids; counting cloud-to-ground lightning density of each grid; calculating lightning stroke tripping risk values of power grid circuits of the to-be-analyzed region; grading the lightning stroke tripping risk values of the power grid circuits of the to-be-analyzed region and performing visualization processing, to obtain a finaldistribution map of lightning stroke tripping risk. Through historical operation data of the power grid and lightning stroke historical data, the to-be-analyzed region is divided by grids, and the lightning stroke tripping risk value of each grid is calculated by using a scientific and reasonable calculation method, to obtain the distribution map of lightning stroke tripping risk. Therefore, the method can accurately and reliably analyze lightning stroke tripping probability, and an analysis process is scientific and reasonable, and analysis effect is good.

The invention relates to a transmission line thunder leading width calculating method based on actually measured lightning stroke data. The transmission line thunder leading width is calculated according to actually measured transmission line body lightning stroke data and thunder positioning system monitoring data. The method mainly comprises the following steps that firstly, the lightning stroke frequency and the cloud-to-ground lightning density of a transmission line body are obtained according to the transmission line body lightning stroke data and the thunder positioning system monitoring data, and secondly, the equivalent thunder leading width is calculated, wherein the computational formula of the equivalent thunder leading width is shown as d=f / rho, and d, f and rho represent the equivalent thunder leading width, the transmission line body lightning stroke frequency and the cloud-to-ground lightning density respectively. In the actual engineering application, compared with an existing method for obtaining the thunder leading width based on the empirical formula, the method has the advantage that the thunder leading width calculated based on the actually measured lightning stroke data is more reliable and accurate.

The invention discloses a distribution decision-making method of a lightning monitoring device of a power distribution network. On the basis of a distribution network lightning location system (LLS),a distribution network fault management system and a distribution network GIS system, an integrated cloud-to-ground lightning density analysis map including a distribution network line and an integrated lightning current amplitude analysis map are drawn by considering thunder-and-lightning and cloud-to-ground lightning density distribution, lightning current amplitude data and historical thunder fault rate of a distribution network line comprehensively; a quantitative analysis is carried out on the monitoring device installation priority based on an analytic hierarchy process; and then a distribution network lightning monitoring device distribution plan is determined by combining actual working conditions. According to the invention, the method has the following advantages: a simple and effective lightning monitoring device distribution plan decision-making method is provided by considering various factors comprehensively and using the analytic hierarchy process; the instructional advice is provided for the lightning monitoring work of the distribution network; the method can match most of existing power supply management systems and has the great practical application value; and the effectiveness and economy of the lightning protection work of the distribution network are improved.

The invention discloses an electric transmission line lightning-protection performance assessment method combined with distributed lightning current monitoring. The method includes the following steps that line corridor lightning characteristic parameters, line characteristic parameters and history lightning stroke fault information are obtained; the tower back striking trip-out rate Pf and tower shield failure trip-out rate Pr of each section under the actual cloud-to-ground lightning intensity are calculated according to the cloud-to-ground lightning intensity of the sections of a line corridor; the lightning trip-out rate assessment index in the electric transmission line operation rule is converted to the average cloud-to-ground lightning intensity of the line, and an actual lightning trip-out rate assessment index S is obtained; S is divided into Sf and Sr according to the occurrence ratio of the back striking trip-out and shield failure trip-out with the history lightning stroke fault information as a reference, and risk grade standards are divided according to the value of Sf and the value of Sr; the intervals of Pf, Pr and risk grades are compared, and the back striking trip-out risk grade and the shield failure trip-out risk grade of each base tower are determined. By the method, the standards of the back striking trip-out risk grade and the shield failure trip-out risk grade can be divided accurately, and the overall lightning-protection performance of the line is assessed.

Methods, systems, and computer program products are described herein for generating proxy reflectivity data associated with lightning activity. A computing device receives data associated with lightning activity for one or more geographical areas. The computing device determines the logarithmic scale of the combined in-cloud and cloud-to-ground flash rate (dBR) for one or more grids of lightning activity based on the received data. The computing device generates proxy reflectivity data based on the dBR of the grids.

The application relates to a cloud-to-ground lightning data assimilation method and system for strong convective weather forecast. According to the application, nonlinear fitting is performed by usingan S-curve function for the plain and mountain areas separately, so as to obtain a new statistical relationship between the lightning frequency and the vertical column maximum proxy radar echo corresponding to the plain and mountain areas; the cloud-to-ground lightning data is converted into a three-dimensional proxy radar echo according to the obtained new statistical relationship; and the three-dimensional proxy radar echo is assimilated into a three-dimensional variational system to realize the assimilation of the cloud-to-ground lightning data. The application greatly improves the accuracy of precipitation prediction and solves the problem of low accuracy of convective system prediction in the prior art.

A system and method for predicting the probability of cloud-to-ground lightning strikes, ‘frequent’, more than 2 strikes per minute on average, cloud to ground lightning strikes, and / or ‘numerous’, more than 4 strikes per minute on average, through the use of polarimetric radar is presented. The data volume created by the polarimetric radar is processed to identify the type of hydrometeors in each range cell. For each vertical column, the maximum height of the graupel is compared to the lowest height of ice crystals in the volume. In the event that the lowest height of ice crystals is ambiguous, the height of the temperature where ice crystals form, −10° C., may be substituted for the lowest height of the ice crystals. Probability density functions are applied to the height difference to determine the probability of cloud to ground lightning within the column. Lightning probability product data are displayed on a visualization system in a georeferenced manner providing georeferenced lightning warnings. A forecast of the probabilities of cloud-to-ground lightning is determined by simple translation using storm track properties.

The invention discloses a high-power cloud-to-ground ion receiving device. The high-power cloud-to-ground ion receiving device includes a warm and humid gas transmission pipeline, a cloud-to-ground ion receiving tower, a conductor absorption pillar, a plasma conductive row, a charge storage and a brim type The equal-voltage equipotential grounding grid replaces the "step leader" function provided by the electric field in the cloud layer, and forms a functional combination of a large closed-loop circuit of cloud-ground ions between the cloud layer and the ground, actively absorbing the lightning current to form the plasma before the lightning strike body, and store the lightning current, so as to completely eliminate lightning strikes, turn lightning current into wealth, and become a natural wealth of human beings, especially suitable for areas where lightning occurs frequently. At the same time, the present invention also provides a method for actively absorbing and storing lightning plasma using the high-power cloud-ground ion receiving device, and storing the lightning plasma in a double-layer or multi-layer graphene capacitor for application.

Systems and methods are disclosed to detect cloud-to-ground (CG) strokes that include or are followed by continuing current. As an example, earth-based lightning data may be generated for one or more lightning pulses detected in an environmental space using multiple earth-based lightning detection sensors. Space-based lightning data may be received for one or more optical signals detected in the environmental space using one or more space-based lightning detection sensors. It may be determined whether one or more lightning pulses is a CG stroke based on the earth-based lightning data. In response to determining that a given one of the one or more lightning pulses is a CG stroke, it may be determined whether the CG stroke includes or is followed by continuing current based on the space-based lightning data.

The invention relates to the field of thunder and lightning protection equipment, in particular to a full-intelligent multi-rotor lifting type active thunder and lightning early warning protection lightning receiving system. The lightning receiving system comprises a multi-rotor aerial automatic stabilization system, an atmospheric electric field monitoring system, a central control system, an aircraft power supply and energy storage system and an aircraft take-off and landing recovery control mechanism. The multi-rotor aerial automatic stabilization system comprises a multi-rotor aircraft and a self-discharge lightning receiving needle mounted on the multi-rotor aircraft. According to the protection lightning arresting system, the multi-rotor aircraft lifts off to a set lightning arresting height and pulls the flexible conductive downlead, so that the self-discharge lightning arresting needle head and thundercloud of a cloud layer are subjected to lightning arresting, and lightning current is guided into the grounding device through the flexible conductive downlead and discharged to the ground. According to the invention, discharge of thunderstorm clouds to ground buildings, personnel, equipment, facilities and the like is reduced and eliminated, lightning stroke disasters caused by direct lightning are reduced, and an active lightning protection effect is achieved.

The present invention provides a three-dimensional thunder-and-lightning fractal structure numerical simulation method applicable to a numerical weather mode. The method comprises the following steps: (1) setting a lightning start breakdown threshold; (2) enabling a lightning to bidirectionally propagate after the lightning is triggered at a start breakdown point, so as to form a lightning propagation channel; (3) determining the type of the lightning; and (4) allocating space charges again. The method provided by the present invention implements numerical simulation of a three-dimensional thunder-and-lightning structure, is capable of simulating a fractal structure similar to natural intracloud flashes and cloud-to-ground, and is capable of simulating a reducing effect of a lightning process on intracloud electric fields.

The invention relates to a digital lightning detection method and a device thereof. The method comprises the following steps: receiving an electromagnetic signal generated when cloud-to-ground flash lightning discharging to generate an electric detection signal; digitalizing the conditioned electric detection signal; filtering the digital signal; establishing a uniform time scale; establishing a lightning signal identification criterion and a digitized cloud-to-ground flash lightning signal identification model by a time determination method, a bipolar test method and a homopolar test method by considering transmission features of a lightning electromagnetic radiation waveform; establishing a time window preprocessing area, and acquiring a development trend of the input digital signal andthe corresponding typical parameters; and computing and determining the parameters of the input digital signal in combination with data in the time window by the digitized cloud-to-ground flash lightning signal identification model . The device consists of an antenna, a signal conditioner, an analog to digital converter, a module of cloud-to-ground flash lightning signal identification model, a system control manager, an assistant control manager, a communication interface, an external memory and a clock.