CN109635360B - Lightning stroke risk assessment method and device based on cascade simulation - Google Patents
Lightning stroke risk assessment method and device based on cascade simulation Download PDFInfo
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Abstract
The application provides a lightning stroke risk assessment method and device based on cascade simulation. The method comprises the following steps: constructing a three-dimensional electric field model and a two-dimensional circuit model of the target area; inputting the three-dimensional electric field model into electromagnetic field simulation software to obtain electromagnetic field distribution in the three-dimensional electric field model under the preset lightning stroke energy; converting the electromagnetic field distribution into a transient pulse waveform; inputting the two-dimensional circuit model into circuit simulation software, and taking the transient pulse waveform as an energy source to acquire circuit response information; and carrying out lightning stroke risk assessment on the target area through the circuit response information. The lightning stroke risk assessment method and device based on the cascade simulation can analyze lightning strokes from multiple angles and improve the power supply reliability of the power distribution network.
Description
Technical Field
The application relates to the field of computer information processing, in particular to a lightning stroke risk assessment method and device based on cascade simulation.
Background
The 10kV and 35kV medium-voltage distribution lines are networks with the widest distribution surface in China and directly distribute electric energy to wide users, and the problems of lightning damage are quite remarkable all the time due to the net-shaped line structure, the limitation of low insulation level and the like. Distribution line faults are essentially caused by lightning accidents, which cause tripping rates that reach almost 2/3 or more of the total tripping rate of the line. The accident of line lightning accident frequently occurs, and the large-area tripping is caused to cause that the distribution lines of some substations are completely jumped during the lightning activity. Lightning damage is a major cause of reduced power supply reliability of the power distribution network.
At present, the field of lightning protection research of distribution lines at home and abroad is immature. The reason for this is that the lightning protection measures of the distribution network are not many, and the distribution network mainly depends on the protection of a lightning arrester and the surge protection of low-voltage installation, so that the line lightning trip of important users cannot be effectively prevented, and electric equipment and microelectronic equipment are damaged. In addition, as the distribution surface of the distribution network is wider, the lightning activity rule and the influence of lightning on the power grid under special topography and meteorological conditions are not completely researched, and a perfect lightning risk assessment and grading system of the distribution network is not established. These problems all create technical arrest in the analysis of lightning strike effects.
Therefore, a new lightning strike risk assessment method and device based on cascade simulation are needed.
The above information disclosed in the background section is only for enhancement of understanding of the background of the disclosure and therefore it may include information that does not form the prior art that is already known to a person of ordinary skill in the art.
Disclosure of Invention
In view of the above, the application discloses a lightning strike risk assessment method and device based on cascade simulation, which can analyze lightning strikes from multiple angles and improve the power supply reliability of a power distribution network.
Other features and advantages of the present disclosure will be apparent from the following detailed description, or may be learned in part by the practice of the disclosure.
According to an aspect of the present disclosure, a lightning strike risk assessment method based on cascade simulation is provided, the method comprising: constructing a three-dimensional electric field model and a two-dimensional circuit model of the target area; inputting the three-dimensional electric field model into electromagnetic field simulation software to obtain electromagnetic field distribution in the three-dimensional electric field model under the preset lightning stroke energy; converting the electromagnetic field distribution into a transient pulse waveform; inputting the two-dimensional circuit model into circuit simulation software, and taking the transient pulse waveform as an energy source to acquire circuit response information; and carrying out lightning stroke risk assessment on the target area through the circuit response information.
In one exemplary embodiment of the present disclosure, constructing a three-dimensional electric field model and a two-dimensional circuit model of a target region includes: constructing a three-dimensional electric field model of the target area through automatic computer aided design software; and/or constructing a two-dimensional circuit model of the target area through electronic design automation design software, wherein the two-dimensional circuit model is an analog circuit model.
In one exemplary embodiment of the present disclosure, inputting the three-dimensional electric field model into electromagnetic field simulation software, acquiring electromagnetic field distribution in the three-dimensional electric field model at a predetermined lightning strike energy includes: determining predetermined lightning stroke energy according to historical lightning stroke data of the target area; inputting the three-dimensional electric field model into electromagnetic field simulation software, and performing electromagnetic field simulation calculation by taking the predetermined lightning stroke energy as a simulation trigger source; and acquiring surface electromagnetic field distribution in the three-dimensional electric field model after calculation is finished.
In one exemplary embodiment of the present disclosure, the electromagnetic field simulation software includes: CST, HFSS, and FEKO.
In one exemplary embodiment of the present disclosure, converting the electromagnetic field distribution into a transient pulse waveform includes: the electromagnetic field distribution is converted into a transient pulse waveform by extracting an equivalent circuit.
In an exemplary embodiment of the present disclosure, inputting the two-dimensional circuit model into circuit simulation software, taking the transient pulse waveform as an energy source, and acquiring circuit response information includes: inputting the two-dimensional circuit model into circuit simulation software, and taking the transient pulse waveform as an equivalent current source to simulate and acquire circuit response information; and/or inputting the two-dimensional circuit model into circuit simulation software, and taking the transient pulse waveform as an equivalent voltage source to simulate and acquire circuit response information.
In one exemplary embodiment of the present disclosure, the circuit simulation software includes: cadence, matlab, and Pspice.
In one exemplary embodiment of the present disclosure, lightning strike risk assessment of the target area by the circuit response information includes: and determining lightning stroke weak points in the target area through the circuit response information.
In one exemplary embodiment of the present disclosure, lightning strike risk assessment of the target area by the circuit response information includes: the probability of single-phase-to-ground and inter-phase shorts in the target region is determined by the circuit response information.
According to an aspect of the present disclosure, there is provided a lightning strike risk assessment device based on cascade simulation, the device comprising: the model module is used for constructing a three-dimensional electric field model and a two-dimensional circuit model of the target area; the three-dimensional electric field module is used for inputting the three-dimensional electric field model into electromagnetic field simulation software to obtain electromagnetic field distribution in the three-dimensional electric field model under the preset lightning stroke energy; a conversion module for converting the electromagnetic field distribution into a transient pulse waveform; the two-dimensional circuit module is used for inputting the two-dimensional circuit model into circuit simulation software, taking the transient pulse waveform as an energy source and acquiring circuit response information; and the risk assessment module is used for carrying out lightning strike risk assessment on the target area through the circuit response information.
According to an aspect of the present disclosure, there is provided an electronic device including: one or more processors; a storage means for storing one or more programs; when the one or more programs are executed by the one or more processors, the one or more processors are caused to implement the methods as described above.
According to an aspect of the present disclosure, a computer-readable medium is presented, on which a computer program is stored, which program, when being executed by a processor, implements a method as described above.
According to the lightning stroke risk assessment method and device based on cascade simulation, through a cascade mode, the lightning stroke effect is simulated and analyzed in a combined mode from the angles of an electromagnetic field and a circuit, and through a mode that the lightning stroke risk is assessed through simulation data, the lightning stroke can be analyzed from multiple angles, and the power supply reliability of the power distribution network is improved.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the disclosure.
Drawings
The above and other objects, features and advantages of the present disclosure will become more apparent by describing in detail exemplary embodiments thereof with reference to the attached drawings. The drawings described below are merely examples of the present disclosure and other drawings may be obtained from these drawings without inventive effort for a person of ordinary skill in the art.
FIG. 1 is a system block diagram illustrating a lightning strike risk assessment method and apparatus based on cascading simulations, according to an example embodiment.
FIG. 2 is a flow chart illustrating a lightning strike risk assessment method based on cascading simulations, according to an example embodiment.
FIG. 3 is a schematic diagram illustrating a lightning strike risk assessment method based on cascading simulations, according to another example embodiment.
FIG. 4 is a block diagram illustrating a lightning strike risk assessment device based on cascading simulations, according to an example embodiment.
Fig. 5 is a block diagram of an electronic device, according to an example embodiment.
FIG. 6 is a schematic diagram illustrating a computer-readable storage medium according to an example embodiment.
Detailed Description
Example embodiments will now be described more fully with reference to the accompanying drawings. However, the exemplary embodiments can be embodied in many forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the concept of the example embodiments to those skilled in the art. The same reference numerals in the drawings denote the same or similar parts, and thus a repetitive description thereof will be omitted.
Furthermore, the described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. In the following description, numerous specific details are provided to give a thorough understanding of embodiments of the disclosure. One skilled in the relevant art will recognize, however, that the disclosed aspects may be practiced without one or more of the specific details, or with other methods, components, devices, steps, etc. In other instances, well-known methods, devices, implementations, or operations are not shown or described in detail to avoid obscuring aspects of the disclosure.
The block diagrams depicted in the figures are merely functional entities and do not necessarily correspond to physically separate entities. That is, the functional entities may be implemented in software, or in one or more hardware modules or integrated circuits, or in different networks and/or processor devices and/or microcontroller devices.
The flow diagrams depicted in the figures are exemplary only, and do not necessarily include all of the elements and operations/steps, nor must they be performed in the order described. For example, some operations/steps may be decomposed, and some operations/steps may be combined or partially combined, so that the order of actual execution may be changed according to actual situations.
It will be understood that, although the terms first, second, third, etc. may be used herein to describe various components, these components should not be limited by these terms. These terms are used to distinguish one element from another element. Accordingly, a first component discussed below could be termed a second component without departing from the teachings of the concepts of the present disclosure. As used herein, the term "and/or" includes any one of the associated listed items and all combinations of one or more.
Those skilled in the art will appreciate that the drawings are schematic representations of example embodiments and that the modules or flows in the drawings are not necessarily required to practice the present disclosure, and therefore, should not be taken to limit the scope of the present disclosure.
The power distribution network has low insulation level, frequent lightning accidents occur, the influence on the power distribution network is larger, and along with the increasing requirements of people on the power supply reliability of the power system, the importance degree of lightning protection of the power system is also higher. In order to reduce lightning accidents and improve the power supply reliability, students at home and abroad continuously apply more new technologies and new materials to power systems. Since the discovery of zinc oxide pressure sensitive characteristics by japanese scholars in the 60 s of the last century, metallic zinc oxide resistive sheets and metallic oxide arresters having excellent volt-ampere characteristics have rapidly developed. Domestic specialists begin to study the characteristics of zinc oxide piezoresistors from the last century, seventies and have conducted a great deal of scientific research foundation work in seventies, and the first batch of metallic zinc oxide arresters are used on 10kV lines in be delirious continents of Hainan. The eighties metal zinc oxide arrester was identified by both committees as the world advanced level, and then the domestic zinc oxide arrester manufacturing industry began to develop rapidly.
Compared with the research of the lightning protection theory and the protection device of the power transmission line, the research field of lightning protection of the power distribution line is obviously immature at home and abroad. The reason for this is that the lightning protection measures of the distribution network are not many, and the distribution network mainly depends on the protection of a lightning arrester and the surge protection of low-voltage installation, so that the line lightning trip of important users cannot be effectively prevented, and electric equipment and microelectronic equipment are damaged. The zinc oxide lightning arrester has obvious advantages, but also has the defects of fixed action voltage and residual voltage parameters, easy aging, easy damage and high running cost, and can not realize the differentiation and fine protection requirements of the power distribution network and equipment except the regular maintenance and replacement. In addition, as the distribution surface of the distribution network is wider, the lightning activity rule and the influence of lightning on the power grid under special topography and meteorological conditions are not completely researched, and a perfect lightning risk assessment and grading system of the distribution network is not established.
Because the differences of the induction overvoltage of the lightning stroke on the three-phase distribution line and the development of simulation software, and because the transient characteristics of the induction overvoltage have larger complexity and randomness, the mathematical modeling is difficult to be completely equivalent to the real lightning characteristics, in the application, the simulation software is struck by the lightning at night in a mode of repeatedly correcting the simulation data combined with the actual experimental data for many times, so that the lightning stroke effect analysis is carried out by the lightning stroke simulation software, and the aims of greatly reducing the lightning stroke tripping rate of the distribution line and improving the operation reliability are achieved.
The details of the present application will be described below with reference to specific examples.
FIG. 1 is a system block diagram illustrating a lightning strike risk assessment method and apparatus based on cascading simulations, according to an example embodiment.
As shown in fig. 1, a system architecture 100 may include terminal devices 101, 102, 103, a network 104, and a server 105. The network 104 is used as a medium to provide communication links between the terminal devices 101, 102, 103 and the server 105. The network 104 may include various connection types, such as wired, wireless communication links, or fiber optic cables, among others.
The user may interact with the server 105 via the network 104 using the terminal devices 101, 102, 103 to receive or send messages or the like. Various communication client applications, such as shopping class applications, web browser applications, search class applications, instant messaging tools, mailbox clients, social platform software, etc., may be installed on the terminal devices 101, 102, 103.
The terminal devices 101, 102, 103 may be a variety of electronic devices having a display screen and supporting web browsing, including but not limited to smartphones, tablets, laptop and desktop computers, and the like.
The server 105 may be a server providing various services, such as a server providing background analysis support for a target object for which a user is to perform risk analysis using the terminal devices 101, 102, 103. The server 105 may perform processing such as analysis on the received target object, and feed back the processing result (risk assessment data) to the terminal device.
The server 105 may, for example, construct a three-dimensional electric field model and a two-dimensional circuit model of the target region; the server 105 may, for example, input the three-dimensional electric field model into electromagnetic field simulation software to obtain electromagnetic field distribution in the three-dimensional electric field model at a predetermined lightning strike energy; the server 105 may, for example, convert the electromagnetic field distribution into a transient pulse waveform; the server 105 may, for example, input the two-dimensional circuit model into circuit simulation software, and obtain circuit response information using the transient pulse waveform as an energy source; the server 105 may perform lightning strike risk assessment on the target area, for example, via the circuit response information.
The server 105 may be an entity server, and may also be a plurality of servers, for example, it should be noted that the lightning risk assessment method based on cascade simulation provided in the embodiments of the present disclosure may be executed by the server 105, and accordingly, the lightning risk assessment device based on cascade simulation may be disposed in the server 105.
FIG. 2 is a flow chart illustrating a lightning strike risk assessment method based on cascading simulations, according to an example embodiment. The lightning risk assessment method 20 based on cascade simulation comprises at least steps S202 to S208.
As shown in fig. 2, in S202, a three-dimensional electric field model and a two-dimensional circuit model of the target region are constructed.
The method for constructing the three-dimensional electric field model and the two-dimensional circuit model of the target area comprises the following steps: constructing a three-dimensional electric field model of the target area through automatic computer aided design software; and/or constructing a two-dimensional circuit model of the target area through electronic design automation design software, wherein the two-dimensional circuit model is an analog circuit model.
Wherein the automated computer aided design software comprises: autoCAD software, electronic design automation design software, includes Cadence.
In S204, the three-dimensional electric field model is input into electromagnetic field simulation software, and electromagnetic field distribution in the three-dimensional electric field model is obtained under predetermined lightning stroke energy.
In one embodiment, inputting the three-dimensional electric field model into electromagnetic field simulation software, and acquiring electromagnetic field distribution in the three-dimensional electric field model under the predetermined lightning stroke energy comprises: determining predetermined lightning stroke energy according to historical lightning stroke data of the target area; inputting the three-dimensional electric field model into electromagnetic field simulation software, and performing electromagnetic field simulation calculation by taking the predetermined lightning stroke energy as a simulation trigger source; and acquiring surface electromagnetic field distribution in the three-dimensional electric field model after calculation is finished.
Wherein the electromagnetic field simulation software comprises: CST, HFSS, and ADS.
Wherein CST, three-dimensional electromagnetic field simulation software. CST is a special simulation software package which is comprehensive, accurate and extremely high in integration level and is oriented to 3D electromagnetic, circuit, temperature and structural stress design engineers. Eight studio sub-software are included, integrated within the same user interface, providing complete system-level and component-level numerical simulation optimization for the user. The software covers the whole electromagnetic frequency band and provides complete time domain and frequency domain full wave electromagnetic algorithm and high frequency algorithm. Typical applications include electromagnetic compatibility, antenna/RCS, high-speed interconnect SI/EMI/PI/eye, cell phone, nuclear magnetic resonance, electrovacuum tube, particle accelerator, high power microwave, nonlinear optics, electrical, field path, electromagnetic-temperature, temperature-deformation, and other various collaborative simulations.
The HFSS is three-dimensional electromagnetic simulation software which is promoted by Ansoft corporation and is purchased by ANSYS corporation at present; is the first commercial three-dimensional structure electromagnetic field simulation software in the world, and is the industry standard for three-dimensional electromagnetic field design and analysis. The HFSS provides a simple and visual user design interface, an accurate self-adaptive field resolver and a powerful post-processor with unprecedented electrical performance analysis capability, and can calculate S parameters and full-wave electromagnetic fields of three-dimensional passive structures with arbitrary shapes. HFSS software has powerful antenna design functions that can calculate antenna parameters such as gain, directivity, far field pattern profile, far field 3D pattern, and 3dB bandwidth; polarization characteristics are plotted, including a spherical field component, a circularly polarized field component, a Ludwig third defined field component, and an axial ratio. HFSS covers all links of high frequency designs.
The FEKO software is powerful three-dimensional full-wave electromagnetic simulation software under the flag of EMSS company. The FEKO method makes it possible to accurately analyze electrical large problems. FEKO supports the Finite Element Method (FEM), and MLFMM and FEM hybrid solutions, MLFMM+FEM hybrid algorithms can solve dielectric large-scale problems with highly non-uniform dielectrics.
Different simulation software can be determined and selected for calculation according to different characteristics of a target area, and simulation analysis can be performed through CST (computer aided manufacturing) isochronous domain electromagnetic field simulation software when simulating an electrically large-size cable in an outdoor environment or a target object such as a lightning rod installed in a high building; while in simulating the scene of lightning protection or power substation equipment such as a power substation, the simulation can be performed by software such as HFSS.
In S206, the electromagnetic field distribution is converted into a transient pulse waveform. The electromagnetic field distribution may be converted into a transient pulse waveform by extracting an equivalent circuit.
In particular, the electromagnetic field distribution may be converted into a transient current waveform, for example, by extracting an equivalent circuit; the electromagnetic field distribution may also be converted into a transient voltage waveform, for example, by extracting an equivalent circuit.
In S208, the two-dimensional circuit model is input into circuit simulation software, and the transient pulse waveform is used as an energy source to obtain circuit response information.
In one embodiment, the two-dimensional circuit model is input into circuit simulation software, and the transient pulse waveform is used as an equivalent current source to simulate and acquire circuit response information.
In one embodiment, the two-dimensional circuit model is input into circuit simulation software, and the transient pulse waveform is used as an equivalent voltage source to simulate and acquire circuit response information.
The circuit simulation software includes: cadence, matlab, and Pspice.
Wherein the Cadence system interconnect platform is capable of co-designing high performance interconnects across integrated circuits, packages, and PCBs. By applying the collaborative design method of the platform, engineers can quickly optimize the system interconnection between I/O buffers and across integrated circuits, packages and PCBs. The method can avoid the reworking of hardware, reduce the cost of hardware and shorten the design period. Constraint-driven Allegro flow includes high-level functionality for design capture, signal integrity, and physical implementation. The Allegro collaborative design method enables efficient design chain collaboration to be realized because the method is also supported by Cadence Encounter and Virtuoso platforms.
The PSPICE software has powerful circuit diagram drawing function, circuit simulation function, graphic post-processing function and component symbol making function, and is input in a graphic mode to automatically perform circuit inspection, generate a chart, simulate and calculate a circuit. The system has very wide application, and can be used for circuit analysis and optimal design, and can also be used for computer-aided teaching of courses such as electronic circuits, signals, systems and the like. The electronic design automation can be realized by matching with printing plate design software.
In S210, lightning strike risk assessment is performed on the target area through the circuit response information.
In one embodiment, a lightning strike weak point in the target area is determined by the circuit response information. In one embodiment, for example, the mechanism of the arc establishment rate of a lightning stroke of the power distribution network and the lightning current have a large amplitude, but have a short wavelength (about 100 mu s) and cannot reach a protection action value, and the line is not tripped, and the reason for tripping the line is that under the action of the power frequency voltage of the power grid, the power frequency freewheels flowing along a channel broken down by the lightning, such as single relative breakdown, and the current is just the capacitance current of the power grid, which is also called the power frequency freewheels.
The probability of whether a stable power frequency short-circuit current can be established after the insulator is struck by lightning is called as the lightning strike arc establishment rate of the power distribution network, the probability is related to the magnitude of the power frequency short-circuit current, whether the probability is larger than the arc extinction critical value of the power grid is needed, and if the probability is single-phase grounding short-circuit current I jd Smaller than the arc extinction critical value I ij (11.4A for a 10kv grid), the temporary arc extinction can be converted into permanent arc extinction because the insulation strength is recovered quickly and is difficult to break down again; when the current is large, the electric arc needs to be extinguished temporarily when the grounding current passes through the zero point each time, when the recovery voltage exceeds the recovery strength, the electric arc is extinguished temporarily for a small time when the recovery voltage exceeds the recovery strength, so that the electric arc can be considered to be stably burnt, and a stable grounding short-circuit electric arc is established. The arc establishment rate eta is related to the average electric field intensity E in the power frequency arc channel and is also related to the instantaneous value of the power frequency voltage at the moment of flashover and the de-ionization condition.
From experimental and operational experience, η may be calculated as follows: η=45e 0.75 -14 (%), where E is the average operating voltage (effective value) gradient of the insulator string, kV/m. System for effectively grounding neutral pointFor a neutral point non-effective grounding system, single-phase flashover does not cause tripping, and interphase flashover is caused to trip only after the second phase conductor is flashover, so thatWherein u is e Rated voltage (effective value) of the line, kV; l (L) 1 The length of the insulator string is m; l (L) 2 For the line-to-line distance of the crossarm lines, m, for the crossarm and reinforced concrete crossarm lines, l 2 ＝0。
And determining lightning weak points in the target area through the circuit response information, researching the distance between the position of the thunderstorm point and the distribution line and the lightning fault of the distribution line in a specific area, calculating the lightning overvoltage amplitude value generated by the distribution line according to the induction lightning overvoltage calculation software generated on the distribution line, evaluating whether the lightning resistance level and the lightning protection measure of the distribution line are reliable or not, and judging whether the insulation weak points exist or not, thereby providing a basis for differential lightning protection.
In one embodiment, the probability of single-phase-to-ground and inter-phase shorts in the target region is determined by the circuit response information.
In another embodiment, the single-phase grounding of the distribution network does not cause line tripping, because the distribution network is not usually provided with zero sequence protection, the distribution network can operate for 2 hours with single-phase grounding faults, the insulation of arc continuous burning dissociation air can be developed into interphase short circuit from single-phase grounding, the line is tripped, and the insulation of insulators can be broken, so that permanent fault points occur to the line insulators; if the power frequency follow current is larger after breakdown, the continuous grounding arc can enable air to generate heat release and light release, multiple circuits erected on the same pole can be affected, and as the distance between each circuit erected on the same pole is smaller, the release of the arc can be affected on other circuits, short-circuit accidents are caused on the multiple circuits erected on the same pole, and when serious, the multiple circuits are tripped simultaneously, so that the power supply reliability of the distribution circuit is greatly affected.
In another embodiment, some mountain area distribution lines towers, because of the very high soil resistivity, are very difficult to reduce the grounding resistance of the towers below the allowable value (10Ω) of the regulations, and at this time, the impact optimization method and device need to be studied from the lightning protection safety point of view, so as to improve the local impact characteristics of the lightning protection grounding device, strengthen the diffusion of lightning current, improve the impact potential distribution and electric field distribution of the grounding device, reduce the impact grounding resistance of the lightning protection grounding device, reduce the lightning overvoltage acting on the protected equipment after the lightning protection device acts, and make it achieve the effective lightning protection effect.
According to the lightning stroke risk assessment method based on cascade simulation, the lightning stroke effect is simulated and analyzed in a combined mode from the angles of an electromagnetic field and a circuit in a cascade mode, lightning stroke risks are assessed through simulation data, lightning strokes can be analyzed from multiple angles, and power supply reliability of the power distribution network is improved.
It should be clearly understood that this disclosure describes how to make and use particular examples, but the principles of this disclosure are not limited to any details of these examples. Rather, these principles can be applied to many other embodiments based on the teachings of the present disclosure.
FIG. 3 is a schematic diagram illustrating a lightning strike risk assessment method based on cascading simulations, according to another example embodiment. FIG. 3 schematically depicts simulation results of a lightning strike effect analysis method. Firstly, constructing a three-dimensional electric field model and a two-dimensional circuit model of a target area; then inputting the three-dimensional electric field model into electromagnetic field simulation software to obtain electromagnetic field distribution in the three-dimensional electric field model under the preset lightning stroke energy; further, converting the electromagnetic field distribution into a transient pulse waveform; then inputting the two-dimensional circuit model into circuit simulation software, and taking the transient pulse waveform as an energy source to acquire circuit response information; and carrying out lightning stroke risk assessment on the target area through the circuit response information.
According to the lightning stroke risk assessment method based on cascade simulation, research results can be implemented on test point lines in the project research process, the lightning stroke tripping rate of the distribution lines is greatly reduced, the lightning stroke tripping rate can be reduced by 50%, the lightning stroke damage rate of distribution equipment is reduced by 80%, and the lightning stroke risk assessment method based on cascade simulation has profound significance in reducing national economic loss, improving company benefits and providing more practical, effective and standard technical standards for power distribution network construction and building smart grids and firm grids.
Those skilled in the art will appreciate that all or part of the steps implementing the above described embodiments are implemented as a computer program executed by a CPU. The above-described functions defined by the above-described methods provided by the present disclosure are performed when the computer program is executed by a CPU. The program may be stored in a computer readable storage medium, which may be a read-only memory, a magnetic disk or an optical disk, etc.
Furthermore, it should be noted that the above-described figures are merely illustrative of the processes involved in the method according to the exemplary embodiments of the present disclosure, and are not intended to be limiting. It will be readily appreciated that the processes shown in the above figures do not indicate or limit the temporal order of these processes. In addition, it is also readily understood that these processes may be performed synchronously or asynchronously, for example, among a plurality of modules.
The following are device embodiments of the present disclosure that may be used to perform method embodiments of the present disclosure. For details not disclosed in the embodiments of the apparatus of the present disclosure, please refer to the embodiments of the method of the present disclosure.
FIG. 4 is a block diagram illustrating a lightning strike risk assessment device based on cascading simulations, according to an example embodiment. The lightning risk assessment device 40 based on cascade simulation includes: a model module 402, a three-dimensional electric field module 404, a transformation module 406, a two-dimensional circuit module 408, and a risk assessment module 410.
The model module 402 is used for constructing a three-dimensional electric field model and a two-dimensional circuit model of the target area; the method for constructing the three-dimensional electric field model and the two-dimensional circuit model of the target area comprises the following steps: constructing a three-dimensional electric field model of the target area through automatic computer aided design software; and/or constructing a two-dimensional circuit model of the target area through electronic design automation design software, wherein the two-dimensional circuit model is an analog circuit model.
The three-dimensional electric field module 404 is configured to input the three-dimensional electric field model into electromagnetic field simulation software, and obtain electromagnetic field distribution in the three-dimensional electric field model under predetermined lightning stroke energy; in one embodiment, inputting the three-dimensional electric field model into electromagnetic field simulation software, and acquiring electromagnetic field distribution in the three-dimensional electric field model under the predetermined lightning stroke energy comprises: determining predetermined lightning stroke energy according to historical lightning stroke data of the target area; inputting the three-dimensional electric field model into electromagnetic field simulation software, and performing electromagnetic field simulation calculation by taking the predetermined lightning stroke energy as a simulation trigger source; and acquiring surface electromagnetic field distribution in the three-dimensional electric field model after calculation is finished.
The conversion module 406 is configured to convert the electromagnetic field distribution into a transient pulse waveform;
the two-dimensional circuit module 408 is configured to input the two-dimensional circuit model into circuit simulation software, and obtain circuit response information by using the transient pulse waveform as an energy source; in one embodiment, the two-dimensional circuit model is input into circuit simulation software, and the transient pulse waveform is used as an equivalent current source to simulate and acquire circuit response information.
In one embodiment, the two-dimensional circuit model is input into circuit simulation software, and the transient pulse waveform is used as an equivalent voltage source to simulate and acquire circuit response information.
The risk assessment module 410 is configured to perform lightning strike risk assessment on the target area through the circuit response information. A lightning weak point in the target area may be determined by the circuit response information. The probability of single-phase-to-ground and inter-phase shorts in the target region may also be determined by the circuit response information.
According to the lightning stroke risk assessment device based on cascade simulation, through a cascade mode, the lightning stroke effect is simulated and analyzed in a combined mode from the angles of an electromagnetic field and a circuit, and through a mode that the lightning stroke risk is assessed through simulation data, the lightning stroke can be analyzed from multiple angles, and the power supply reliability of the power distribution network is improved.
Fig. 5 is a block diagram of an electronic device, according to an example embodiment.
An electronic device 200 according to such an embodiment of the present disclosure is described below with reference to fig. 5. The electronic device 200 shown in fig. 5 is merely an example and should not be construed to limit the functionality and scope of use of embodiments of the present disclosure in any way.
As shown in fig. 5, the electronic device 200 is in the form of a general purpose computing device. The components of the electronic device 200 may include, but are not limited to: at least one processing unit 210, at least one memory unit 220, a bus 230 connecting the different system components (including the memory unit 220 and the processing unit 210), a display unit 240, and the like.
Wherein the storage unit stores program code executable by the processing unit 210 such that the processing unit 210 performs steps according to various exemplary embodiments of the present disclosure described in the above-described electronic prescription flow processing methods section of the present specification. For example, the processing unit 210 may perform the steps as shown in fig. 2.
The memory unit 220 may include readable media in the form of volatile memory units, such as Random Access Memory (RAM) 2201 and/or cache memory 2202, and may further include Read Only Memory (ROM) 2203.
The storage unit 220 may also include a program/utility 2204 having a set (at least one) of program modules 2205, such program modules 2205 including, but not limited to: an operating system, one or more application programs, other program modules, and program data, each or some combination of which may include an implementation of a network environment.
Bus 230 may be a bus representing one or more of several types of bus structures including a memory unit bus or memory unit controller, a peripheral bus, an accelerated graphics port, a processing unit, or a local bus using any of a variety of bus architectures.
The electronic device 200 may also communicate with one or more external devices 300 (e.g., keyboard, pointing device, bluetooth device, etc.), one or more devices that enable a user to interact with the electronic device 200, and/or any device (e.g., router, modem, etc.) that enables the electronic device 200 to communicate with one or more other computing devices. Such communication may occur through an input/output (I/O) interface 250. Also, the electronic device 200 may communicate with one or more networks such as a Local Area Network (LAN), a Wide Area Network (WAN), and/or a public network, such as the Internet, through a network adapter 260. Network adapter 260 may communicate with other modules of electronic device 200 via bus 230. It should be appreciated that although not shown, other hardware and/or software modules may be used in connection with electronic device 200, including, but not limited to: microcode, device drivers, redundant processing units, external disk drive arrays, RAID systems, tape drives, data backup storage systems, and the like.
From the above description of embodiments, those skilled in the art will readily appreciate that the example embodiments described herein may be implemented in software, or may be implemented in software in combination with the necessary hardware. Thus, the technical solution according to the embodiments of the present disclosure may be embodied in the form of a software product, which may be stored in a non-volatile storage medium (may be a CD-ROM, a U-disk, a mobile hard disk, etc.) or on a network, including several instructions to cause a computing device (may be a personal computer, a server, or a network device, etc.) to perform the above-described method according to the embodiments of the present disclosure.
Fig. 6 schematically illustrates a computer-readable storage medium in an exemplary embodiment of the present disclosure.
Referring to fig. 6, a program product 400 for implementing the above-described method according to an embodiment of the present disclosure is described, which may employ a portable compact disc read-only memory (CD-ROM) and include program code, and may be run on a terminal device, such as a personal computer. However, the program product of the present disclosure is not limited thereto, and in this document, a readable storage medium may be any tangible medium that can contain, or store a program for use by or in connection with an instruction execution system, apparatus, or device.
The program product may employ any combination of one or more readable media. The readable medium may be a readable signal medium or a readable storage medium. The readable storage medium can be, for example, but is not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or a combination of any of the foregoing. More specific examples (a non-exhaustive list) of the readable storage medium would include the following: an electrical connection having one or more wires, a portable disk, a hard disk, random Access Memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.
The computer readable storage medium may include a data signal propagated in baseband or as part of a carrier wave, with readable program code embodied therein. Such a propagated data signal may take any of a variety of forms, including, but not limited to, electro-magnetic, optical, or any suitable combination of the foregoing. A readable storage medium may also be any readable medium that can communicate, propagate, or transport a program for use by or in connection with an instruction execution system, apparatus, or device. Program code embodied on a readable storage medium may be transmitted using any appropriate medium, including but not limited to wireless, wireline, optical fiber cable, RF, etc., or any suitable combination of the foregoing.
Program code for carrying out operations of the present disclosure may be written in any combination of one or more programming languages, including an object oriented programming language such as Java, C++ or the like and conventional procedural programming languages, such as the "C" programming language or similar programming languages. The program code may execute entirely on the user's computing device, partly on the user's device, as a stand-alone software package, partly on the user's computing device, partly on a remote computing device, or entirely on the remote computing device or server. In the case of remote computing devices, the remote computing device may be connected to the user computing device through any kind of network, including a Local Area Network (LAN) or a Wide Area Network (WAN), or may be connected to an external computing device (e.g., connected via the Internet using an Internet service provider).
The computer-readable medium carries one or more programs, which when executed by one of the devices, cause the computer-readable medium to perform the functions of: constructing a three-dimensional electric field model and a two-dimensional circuit model of the target area; inputting the three-dimensional electric field model into electromagnetic field simulation software to obtain electromagnetic field distribution in the three-dimensional electric field model under the preset lightning stroke energy; converting the electromagnetic field distribution into a transient pulse waveform; inputting the two-dimensional circuit model into circuit simulation software, and taking the transient pulse waveform as an energy source to acquire circuit response information; and carrying out lightning stroke risk assessment on the target area through the circuit response information.
Those skilled in the art will appreciate that the modules may be distributed throughout several devices as described in the embodiments, and that corresponding variations may be implemented in one or more devices that are unique to the embodiments. The modules of the above embodiments may be combined into one module, or may be further split into a plurality of sub-modules.
From the above description of embodiments, those skilled in the art will readily appreciate that the example embodiments described herein may be implemented in software, or in combination with the necessary hardware. Thus, the technical solutions according to the embodiments of the present disclosure may be embodied in the form of a software product, which may be stored in a non-volatile storage medium (may be a CD-ROM, a U-disk, a mobile hard disk, etc.) or on a network, and include several instructions to cause a computing device (may be a personal computer, a server, a mobile terminal, or a network device, etc.) to perform the method according to the embodiments of the present disclosure.
Claims (9)
1. A lightning stroke risk assessment method based on cascade simulation is characterized by comprising the following steps:
constructing a three-dimensional electric field model and a two-dimensional circuit model of the target area;
inputting the three-dimensional electric field model into electromagnetic field simulation software to obtain electromagnetic field distribution in the three-dimensional electric field model under the preset lightning stroke energy;
converting the electromagnetic field distribution into a transient pulse waveform;
inputting the two-dimensional circuit model into circuit simulation software, and taking the transient pulse waveform as an energy source to acquire circuit response information; and
carrying out lightning stroke risk assessment on the target area through the circuit response information;
the lightning strike risk assessment of the target area through the circuit response information comprises the following steps:
determining lightning weak points in the target area through the circuit response information;
and calculating the lightning overvoltage amplitude value generated by the distribution line according to the calculation software for generating the induced lightning overvoltage on the distribution line, and evaluating whether the lightning resistance level and the lightning protection measure of the distribution line are reliable or not and whether an insulation weakness exists or not.
2. The method of claim 1, wherein constructing a three-dimensional electric field model and a two-dimensional circuit model of the target region comprises:
constructing a three-dimensional electric field model of the target area through automatic computer aided design software; and/or
And constructing a two-dimensional circuit model of the target area through electronic design automation design software, wherein the two-dimensional circuit model is an analog circuit model.
3. The method of claim 1, wherein inputting the three-dimensional electric field model into electromagnetic field simulation software to obtain electromagnetic field distribution in the three-dimensional electric field model at a predetermined lightning strike energy comprises:
determining predetermined lightning stroke energy according to historical lightning stroke data of the target area;
inputting the three-dimensional electric field model into electromagnetic field simulation software, and performing electromagnetic field simulation calculation by taking the predetermined lightning stroke energy as a simulation trigger source; and
and acquiring the surface electromagnetic field distribution in the three-dimensional electric field model after the calculation is finished.
4. A method as claimed in claim 3, wherein the electromagnetic field simulation software comprises:
CST, HFSS, and FEKO.
5. The method of claim 1, wherein converting the electromagnetic field distribution into a transient pulse waveform comprises: the electromagnetic field distribution is converted into a transient pulse waveform by extracting an equivalent circuit.
6. The method of claim 1, wherein inputting the two-dimensional circuit model into circuit simulation software, taking the transient pulse waveform as an energy source, obtaining circuit response information comprises:
inputting the two-dimensional circuit model into circuit simulation software, and taking the transient pulse waveform as an equivalent current source to simulate and acquire circuit response information; and/or
Inputting the two-dimensional circuit model into circuit simulation software, and taking the transient pulse waveform as an equivalent voltage source to simulate and acquire circuit response information.
7. The method of claim 6, wherein the circuit simulation software comprises:
cadence, matlab, and Pspice.
8. The method of claim 1, wherein lightning strike risk assessment of the target area by the circuit response information comprises:
the probability of single-phase-to-ground and inter-phase shorts in the target region is determined by the circuit response information.
9. A lightning strike risk assessment device based on cascade simulation, comprising:
the model module is used for constructing a three-dimensional electric field model and a two-dimensional circuit model of the target area;
the three-dimensional electric field module is used for inputting the three-dimensional electric field model into electromagnetic field simulation software to obtain electromagnetic field distribution in the three-dimensional electric field model under the preset lightning stroke energy;
a conversion module for converting the electromagnetic field distribution into a transient pulse waveform;
the two-dimensional circuit module is used for inputting the two-dimensional circuit model into circuit simulation software, taking the transient pulse waveform as an energy source and acquiring circuit response information; and
the risk assessment module is used for carrying out lightning strike risk assessment on the target area through the circuit response information; the lightning strike risk assessment of the target area through the circuit response information comprises the following steps:
determining lightning weak points in the target area through the circuit response information;
and calculating the lightning overvoltage amplitude value generated by the distribution line according to the calculation software for generating the induced lightning overvoltage on the distribution line, and evaluating whether the lightning resistance level and the lightning protection measure of the distribution line are reliable or not and whether an insulation weakness exists or not.
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| CN110516397B (en) * | 2019-09-02 | 2022-12-27 | 南华大学 | Method and system for simulating thunder electromagnetic environment |
| CN110889157A (en) * | 2019-11-18 | 2020-03-17 | 深圳智润新能源电力勘测设计院有限公司 | Wind power plant layout visualization display method and related device |
| CN112182847B (en) * | 2020-09-04 | 2024-04-16 | 南方电网科学研究院有限责任公司 | Pilot length proportional relation-based pilot development model building method and device |
| CN112199841A (en) * | 2020-09-30 | 2021-01-08 | 海南电网有限责任公司电力科学研究院 | Simulation calculation method for differential evaluation of lightning damage |
| CN112595938B (en) * | 2020-12-03 | 2023-08-22 | 河南四达电力设备股份有限公司 | Method for evaluating adaptability of graphite-based flexible grounding device of pole tower of overhead transmission line |
| CN112651159A (en) * | 2020-12-25 | 2021-04-13 | 广东电网有限责任公司电力科学研究院 | High-voltage cross-connection cable joint transient electric stress assessment method |
| CN112924763B (en) * | 2021-01-27 | 2023-04-11 | 国网河北省电力有限公司超高压分公司 | Method for evaluating transient electric shock below high-voltage alternating-current transmission line |
| CN113406726B (en) * | 2021-06-01 | 2022-09-27 | 中国石油大学(北京) | Oil and gas station lightning accident early warning method, device, equipment and storage medium |
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