Lightning protection configuration method for power transmission line

Abstract

The invention relates to the technical field of power grid management, in particular to a power transmission line lightning protection configuration method, which comprises the following steps: acquiring a lightning stroke transient simulation model based on line electrical and structural parameters; secondly, obtaining counterattack and shielding failure lightning-proof data through simulation in combination with the maximum lightning-proof bearing value; then, calculating corresponding counterattack and shielding failure trip-out rates based on the lightning-proof data; and finally, taking the two trip-out rates as core configuration indexes to generate and optimize a lightning protection configuration scheme of the power transmission line. According to the method, the lightning protection configuration is converted from experience driving to data driving through simulation quantitative evaluation, the lightning protection effect and economical efficiency can be scientifically and accurately balanced, and the lightning protection performance and the operation reliability of the line are effectively improved.

Description

Technical Field

[0001] This invention relates to the field of power grid management technology, and in particular to a method for configuring lightning protection for transmission lines. Background Technology

[0002] Lightning protection for overhead transmission lines is a crucial aspect of ensuring power grid reliability, especially for ultra-high voltage (UHV) and extra-high voltage (EHV) transmission lines. Existing technologies improve lightning protection capabilities through measures such as installing lightning protection wires, strengthening insulation, reducing protection angles, and lowering tower grounding resistance; however, lightning-induced power outages still occur frequently.

[0003] Among existing related technologies, installing surge arresters or surge insulators is an effective supplementary means of lightning protection. However, traditional methods for configuring lightning protection devices lack systematic evaluation indicators, making it difficult to achieve optimal parameter configuration. How to balance lightning protection effectiveness and economy, and rationally select current-carrying parameters, remains a pressing technical challenge. Summary of the Invention

[0004] To address the aforementioned technical problems, this invention provides a method for configuring lightning protection for power transmission lines.

[0005] According to one aspect of the present invention, a method for configuring lightning protection for transmission lines is provided, comprising: A transient simulation model of lightning strikes on a transmission line is obtained, which is derived from the electrical and structural parameters of the transmission line. Based on the aforementioned lightning transient simulation model, and combined with the maximum lightning protection withstand value of the transmission line, backflashover lightning withstand data and swirlover lightning withstand data are obtained. Based on the lightning protection data, the corresponding lightning trip rate is obtained; Based on the backflashover resistance data, the corresponding backflashover trip rate is obtained; The backflashover trip rate and the backflashover trip rate are used as configuration indicators to generate the lightning protection configuration for transmission lines.

[0006] According to another aspect of the present invention, a lightning protection configuration device for transmission lines includes: The simulation model acquisition module is used to acquire the lightning transient simulation model of the transmission line, which is based on the electrical and structural parameters of the transmission line. The lightning withstand level calculation module is used to obtain backflash lightning withstand data and swirl lightning withstand data of the transmission line based on the lightning transient simulation model and the maximum lightning withstand value of the transmission line. The tripping rate calculation module is used to obtain the corresponding tripping rate based on the lightning protection data and the corresponding backflashover tripping rate based on the lightning protection data. The configuration determination module is used to determine the lightning protection configuration of the transmission line by using the backflashover trip rate and the backflashover trip rate as configuration indicators.

[0007] The technical solution provided by the embodiments of the present invention has the following advantages compared with the prior art: This invention overcomes the limitations of traditional methods that rely on simplified models or empirical formulas by constructing a transient lightning strike simulation model based on real parameters, ensuring high accuracy at the source of analysis. Secondly, by combining clear withstand value criteria, it quantifies the lightning withstand capability of lines into precise lightning withstand data, establishing an objective and unified evaluation benchmark, making the performance comparison of different lightning protection schemes clear and fair. Crucially, this method successfully transforms the technical level of lightning withstand capability into the tripping rate risk indicator most concerning to power grid operators, bridging the gap between technical parameters and operational risks, and greatly enhancing the practical value of the analysis results. Finally, using the tripping rate as the core configuration indicator, it achieves optimized decision-making and closed-loop management of lightning protection schemes. Attached Figure Description

[0008] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0009] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0010] Figure 1 This is a schematic diagram of the method flow of the present invention; Figure 2 This is a schematic diagram of the electrical geometric model structure analysis for calculating the exposure distance and the backlash rate according to an embodiment of the present invention; Figure 3 This is a schematic diagram of the process for obtaining the tripping rate according to an embodiment of the present invention; Figure 4 This is a schematic diagram of the structure of the electronic device described in an embodiment of the present invention; Figure 5 This is a schematic diagram of the device described in an embodiment of the present invention. Detailed Implementation

[0011] To better understand the above-mentioned objectives, features, and advantages of the present invention, the solutions of the present invention will be further described below. It should be noted that, unless otherwise specified, the embodiments of the present invention and the features thereof can be combined with each other.

[0012] Many specific details are set forth in the following description in order to provide a full understanding of the invention, but the invention may also be practiced in other ways different from those described herein; obviously, the embodiments in the specification are only some embodiments of the invention, and not all embodiments.

[0013] This embodiment provides a specific application scenario for a lightning protection configuration method for transmission lines. (See attached document.) Figure 1 This section details the entire process of the method.

[0014] Step S100: Obtain the lightning transient simulation model of the transmission line. The lightning transient simulation model of the transmission line is obtained using the electrical and structural parameters of the transmission line.

[0015] The construction of this simulation model relies entirely on the electrical and structural parameters of the target transmission line. The electrical parameters encompass the line's voltage level, conductor and ground wire types, distributed parameters such as resistance, inductance, and capacitance per unit length, and key physical properties such as the earth resistivity along the line. The structural parameters define the line's physical form in detail, including the type and geometry of the towers, the relative positions of the conductors and lightning protection wires in space (horizontal and vertical spacing), the line's protection angle, the configuration and insulation strength of the insulator strings, and the span length.

[0016] By inputting these real-world parameters into a professional electromagnetic transient simulation software platform, a lightning strike transient simulation model that reflects the actual physical characteristics of the line is established. This model has high fidelity and can accurately simulate the complex wave process, electromagnetic coupling, and overvoltage propagation and refraction in the network after lightning current injection, providing a reliable and accurate digital test environment for subsequent lightning withstand performance evaluation.

[0017] Step S200: Based on the lightning transient simulation model and combined with the maximum lightning protection withstand value of the transmission line, obtain backflashover lightning withstand data and swirlover lightning withstand data.

[0018] In this step, the maximum lightning withstand value is used as the evaluation criterion. This withstand value is a predetermined critical threshold representing the maximum capability of the line lightning protection system (including insulators and lightning protection devices) to maintain functional integrity without damage or line tripping when struck by lightning. In the simulation model, the lightning withstand level is determined by simulating two typical lightning strike scenarios: first, simulating lightning striking a tower or lightning conductor (i.e., backflashover scenario); second, simulating lightning bypassing the lightning conductor and striking the conductor directly (i.e., bypassing the lightning conductor scenario). In each scenario, by gradually injecting lightning currents of different amplitudes and closely monitoring the system's response, when the electrical state of the line reaches or exceeds the preset "maximum lightning withstand value," the corresponding lightning current amplitude is recorded as the backflashover lightning withstand level or bypassing lightning withstand level under that configuration. The resulting dataset constitutes a direct technical indicator for measuring the line's robustness against lightning strikes.

[0019] Step S300: Based on the lightning protection data, obtain the corresponding lightning protection trip rate; based on the lightning protection data, obtain the corresponding lightning backflashover trip rate.

[0020] This step aims to transform the lightning withstand level data obtained in step S200, based on specific lightning current amplitudes, into more macroscopically instructive statistical indicators—the backflashover tripping rate and the bypass tripping rate related to lightning strikes. The tripping rate comprehensively reflects both the line's own lightning withstand performance and the frequency of external lightning activity.

[0021] Based on the acquired backflashover and lightning strike resistance data, this step will calculate the backflashover tripping rate and the lightning strike tripping rate separately. The calculation process is not a simple linear transformation, but requires the integration of mature engineering algorithms and statistical models. For example, the calculation of the backflashover tripping rate comprehensively considers multiple factors such as the line's lightning attraction width, the impact of terrain on the strike rate, the arc-building rate of insulators, and the ground flash density in the area where the line is located. Similarly, the calculation of the lightning strike tripping rate requires the use of an electrical geometric model, combined with structural parameters such as the line's protection angle and conductor height, to assess the probability of lightning striking the conductor while it is behind the conductor. Through these comprehensive calculations, the technical lightning resistance level is transformed into the expected fault frequency at the operational level, providing a scientific and objective basis for subsequent configuration decisions.

[0022] Step S400: Use the backflashover tripping rate and the backflashover tripping rate as configuration indicators to generate and issue the lightning protection configuration parameters for the transmission line.

[0023] In this step, the backflashover trip rate and bypass trip rate calculated in step S300 will be used as core configuration indicators.

[0024] These indicators are directly used to evaluate and compare different lightning protection configuration schemes. The configuration process is essentially an optimization process: based on preset lightning protection objectives, such as controlling the total lightning trip rate below a certain standard value, different types and parameters of lightning protection device combinations are examined, their corresponding trip rates are calculated, and combined with economic analysis, one or more configuration schemes that achieve the best balance between lightning protection effectiveness and investment cost are finally determined. The final generated transmission line lightning protection configuration parameters are specific and detailed, specifying not only the selection and specifications of lightning protection devices but also potentially including key information such as their installation location and method. This configuration scheme will be distributed in a standardized digital file format to relevant line design, procurement, or operation and maintenance management systems, directly guiding project implementation and thus realizing a scientific shift in lightning protection configuration from experience-driven to data-driven.

[0025] In some embodiments, obtaining the corresponding backflashover trip rate and bypass trip rate includes: obtaining the backflashover trip rate using the procedure method based on backflashover lightning withstand data and bypass lightning withstand data; see reference Figure 2Based on backflashover lightning protection data and lightning protection data with snagging lightning protection, the snagging trip rate is obtained using the electrical geometric model exposure distance method.

[0026] Specifically, the backflashover tripping rate is obtained based on backflashover lightning withstand data and calculated using industry-recognized standard methods. This method comprehensively considers multiple factors, including the line's lightning strike width, the influence of terrain on the strike rate, the arc-building rate of insulators, and the ground flash density in the line's area. Key parameters such as ground flash density and cumulative lightning current probability curves can be obtained from long-term statistical data provided by local lightning location systems, ensuring that the calculation results closely reflect the actual operating environment of the line.

[0027] The tripping rate due to lightning strikes is obtained based on lightning withstand data and calculated using a more refined electrical geometric model exposure distance method. This method no longer treats lightning strikes as a random event, but rather, based on geometric principles, analyzes the electrical distance relationship between the lightning conductor, the conductor, and the ground to accurately assess the probability of lightning bypassing the lightning conductor and directly striking the conductor. Its core lies in calculating an "exposure distance," which is the dangerous area where the lightning leader might strike the conductor. Combined with the lightning current probability distribution, the tripping rate due to lightning strikes is finally obtained through integration, providing a scientific quantitative basis for lightning strike protection.

[0028] The formula for calculating the trip rate of each phase conductor of an AC transmission line or each pole of a DC transmission line is as follows:

[0029] In the formula, Ng Lightning strike density, I c This refers to the lightning withstand level of the conductor in this phase. I max Zs represents the maximum inrush current, and Zs is the exposure distance of the conductor in that phase. f ( I Let be the probability distribution density function of the lightning current. Then the tripping rate of the entire transmission line is the sum of the tripping rates of each phase or each pole.

[0030] In some embodiments, using backflashover tripping rate and side-strike tripping rate as configuration indicators aims to obtain a macroscopic indicator that truly reflects the overall lightning protection performance of the entire transmission line through refined and differentiated evaluation. In this embodiment, if the differences in lightning strike characteristics of the entire transmission line are further considered, the entire transmission line can be divided into segments for calculation. The segmentation principle can be based on key differences such as the topography along the line (e.g., mountainous areas, plains, hills), lightning activity intensity (e.g., areas with frequent lightning strikes, areas with few lightning strikes), or tower structure type. The tripping rate of each segment is calculated, that is, the tripping rate calculation process is executed independently for each segment, thereby obtaining the backflashover tripping rate and side-strike tripping rate of the segmented transmission line. Specifically, the process can be summarized in the following steps: obtain the segmented transmission lines; based on the backflashover and lightning withstand data of the segmented transmission lines, obtain the backflashover tripping rate and lightning withstand rate of the segmented transmission lines; obtain the total lightning tripping rate of the transmission lines, which is obtained by weighted averaging of the backflashover and lightning withstand rates of the segmented transmission lines, and the total lightning tripping rate is used as the configuration index for lightning protection of the transmission lines.

[0031] In this embodiment, the traditional approach of treating the entire line as a homogeneous entity is abandoned, and instead, segmented transmission lines are obtained. The segmentation principle can be based on key differences such as the topography along the line, such as mountains, plains, hills, lightning activity intensity, such as areas with frequent lightning, areas with few lightning, or tower structure type.

[0032] Next, for each segment, based on the backflashover and lightning withstand data of that segment's transmission line, an independent tripping rate calculation process is performed to obtain the backflashover and lightning withstand rates of the segment's transmission line. This process ensures that the assessment of each segment matches its own characteristics and risks.

[0033] Finally, to arrive at a comprehensive conclusion, the total lightning trip rate of the transmission line needs to be obtained. This total rate is not a simple arithmetic mean, but rather a weighted average of the backflashover trip rate and the bypass trip rate of the segmented transmission lines. The weight is typically the length of each segment, reflecting the lightning characteristics of the transmission line and serving as an indicator for selecting the current-carrying parameters of surge arresters or lightning protection insulators. This more scientifically reflects the overall risk level of long-distance lines. This total lightning trip rate is ultimately established as the configuration index for the lightning protection configuration of the transmission line, providing the most direct and reliable basis for subsequent optimization and decision-making regarding lightning protection schemes.

[0034] In some embodiments, the lightning transient simulation model is a local transmission line simulation model. In this embodiment, this choice is based on an optimal balance between computational accuracy and resource consumption. Constructing a full-size model covering the entire line, which is hundreds or even thousands of kilometers long, is computationally extremely time-consuming and impractical.

[0035] Therefore, in this embodiment, a "point-to-surface" strategy is adopted, selecting representative continuous sections of the line for modeling. Based on engineering experience and simulation verification, a local transmission line model is generally established, and setting the number of towers to 9 to 11 is sufficient to obtain adequate accuracy. To eliminate model boundary effects and ensure the accuracy of simulation results, equivalent power sources and equivalent loads are set at both ends of this local model to simulate the actual situation of connecting to an infinitely long line. This local modeling method not only ensures the accurate reproduction of key electromagnetic transient processes but also significantly improves computational efficiency, making large-scale parametric scanning and optimization possible.

[0036] In some embodiments, simulation results of the impulse corona effect are obtained through simulation processing of a local transmission line simulation model. This is a key step in improving the model fidelity. During the wavefront stage of a lightning overvoltage, the electric field strength on the conductor surface may exceed the breakdown strength of air, thereby triggering corona discharge. This physical phenomenon significantly alters the distributed capacitance of the line, causing the overvoltage wave to attenuate and deform during propagation. Ignoring this phenomenon will lead to overly optimistic lightning withstand level assessments.

[0037] Therefore, in this embodiment, the impact corona effect of the transmission line is considered by introducing a specialized corona simulation algorithm into the local transmission line simulation model, thereby obtaining the simulation results of the impact corona effect. This result quantifies the impact of corona discharge on the wave process, enabling the simulation model to more realistically reflect the physical world, thus providing more reliable and accurate input data for subsequent lightning withstand level calculations and tripping rate assessments.

[0038] In some embodiments, the acquisition of simulation results for the impact corona effect is specifically as follows: First, in model construction, based on the simulated transmission line, several parallel segmented simulated transmission lines are acquired; an equivalent simulation circuit is acquired, and the impact corona of the segmented simulated transmission lines is obtained using the equivalent simulation circuit; wherein, the equivalent simulation circuit is obtained by connecting a diode, a voltage-controlled switch, and an additional capacitor in series. Here, the diode is used to simulate the unidirectional conduction characteristic of the current, the starting voltage of the voltage-controlled switch is precisely set according to the initial corona voltage of the conductor, and the additional capacitor is used to simulate the dynamic capacitance effect of the corona sheath. Based on the conductor geometric parameters of the segmented simulated transmission line, such as conductor radius and spacing between split conductors, the impact corona parameters of the equivalent simulation circuit, such as the additional capacitance value and the operating voltage of the voltage-controlled switch, are obtained through theoretical calculations or empirical formulas. After incorporating these parameterized circuits into the local transmission line simulation model, the generation and development of impact corona can be dynamically simulated during the simulation process, ultimately generating simulation results for the impact corona effect.

[0039] In some embodiments, the maximum lightning withstand value provides a clear and engineered criterion for the entire lightning withstand level assessment process. In lightning strike simulation, determining how to determine if the line's protection capability has reached its limit requires a quantitative standard: using the maximum lightning withstand value in the historical lightning protection configuration of the transmission line as the criterion, the backflashover lightning withstand data and the backflashover lightning withstand data of the transmission line are obtained.

[0040] In this embodiment, the criterion is specifically set as follows: based on the maximum lightning withstand value in the historical lightning protection configuration of the transmission line. In engineering practice, this is usually specified as: using the maximum energy absorbed by the lightning protection device, such as a surge arrester or lightning insulator, as the criterion. During the simulation, the current flowing through the lightning protection device and its accumulated absorbed energy are continuously monitored. Once the energy absorption value reaches the rated maximum withstand value of the device, the corresponding lightning current amplitude is determined to be the backflashover level or bypass level of the line under this configuration. This criterion is directly related to the physical limits of the lightning protection device, giving the evaluation results clear physical meaning and engineering guidance value.

[0041] In some embodiments, the exposure distance method of electrical geometry model is used to obtain the bypass trip rate, such as... Figure 2 A schematic diagram of the electrical geometric model analysis for calculating the tripping rate due to exposure distance. The shielding arc EA, the exposure arc AB, and the ground strike distance line BF intersect at A(x). A ,y A B(x) B ,y B Establish a coordinate system XOY based on two points, with the point where the lightning protection wire is located as the origin O of the coordinate system. The straight line parallel to the ground passing through the origin is the X-axis, and the straight line perpendicular to the ground is the Y-axis. ss r sc r sg denoted as strike distances of the lightning conductor, conductor, and ground, respectively; hss and hsc represent the heights of the lightning conductor and conductor above the ground, respectively; d represents the distance between the lightning conductor and conductor; θ represents the protection angle; and Zs represents the exposure distance.

[0042] The formula for calculating the strike distance can be the one recommended by the IEEE (Institute of Electrical and Electronics Engineers) guidelines, where the strike distance r of the lightning conductor is... ss The calculation formula is as follows:

[0043] In the formula, r ss I represents the strike distance of the lightning conductor; I represents the amplitude of the lightning current, in kA.

[0044] The formula for calculating the distance of a lightning strike to the ground is as follows:

[0045] In the formula, r sg The earth strike distance is measured in meters. hsc The average height of the conductor is expressed in meters (m).

[0046] Wire distance formula:

[0047] In the formula, r sc The conductor striking distance is in meters. U DC This represents the operating voltage of the conductor, measured in kV.

[0048] First, if intersection points A and B exist, the coordinates of intersection points A and B can be obtained by solving the equations of the circles containing the shielding arc and the exposed arc, and by solving the equations of the exposed arc and the line connecting the earth's impact distance. The formulas are as follows:

[0049]

[0050]

[0051] in, .

[0052] The tripping rate is obtained based on a four-condition exposure distance classification method. Traditional electrical geometry models often use simplified exposure distance calculation formulas when dealing with complex line structures and variable lightning currents, which may lead to significant errors.

[0053] In this embodiment, a four-condition classification is introduced to achieve accurate identification of the geometric shape of the exposure distance. Instead of using a single formula, the composition of the exposure distance is first logically classified based on the magnitude of the lightning current and line structure parameters. This classification comprehensively covers all possible geometric scenarios, such as whether the shielding arc and the exposure arc intersect, and whether the ground strike distance affects the exposure arc. This pre-classification ensures the accuracy of subsequent exposure distance calculations, thus laying a solid foundation for the accurate assessment of the bypass tripping rate. The four conditions are as follows: The four conditions are as follows: 1. Distance between lightning protection wire and conductor d The sum of the strike distances of the lightning protection wire and the conductor ( r ss + r sc The size relationship (intersection points) A Does it exist? 2. Horizontal spacing between lightning protection wires and conductors dsinθ The sum of the strike distances of the lightning protection wire and the conductor ( r ss + r sc The size relationship of the shielding arc to the exposed arc in the horizontal direction. 3. Ground strike distance r sg relative height of the conductor to the ground hsc Size relationship (intersection point) B The x-axis is... x B and dsinθ + r sc (size relationship) 4. The ordinate of point A y A Relationship with 0 (intersection point) A The x-coordinate is... A and r ss (size relationship).

[0054] Then, based on the judgment of the four conditions, the formulas for calculating the exposure distance under all eight possible scenarios can be obtained. When d > r ss + r sc , dsinθ> r ss + r sc , r sg < h sc The formula for calculating exposure distance is as follows:

[0055] when d > r ss + r sc , dsinθ> r ss + r sc , r sg h sc The formula for calculating exposure distance is as follows:

[0056] when d > r ss + r sc, dsinθ < r ss + r sc , r sg <h sc When, the exposure distance calculation formula is as follows:

[0057] When d > r ss + r sc , dsinθ < r ss + r sc , r sg > h sc When, the exposure distance calculation formula is as follows:

[0058] When d < r ss + r sc , rsg < hsc, yA < 0, the exposure distance calculation formula is as follows:

[0059] When d < r ss + r sc , rsg < hsc, yA > 0, the exposure distance calculation formula is as follows:

[0060] When d < r ss + r sc , rsg > hsc, yA < 0, the exposure distance calculation formula is as follows:

[0061] When d < r ss + r sc , rsg > hsc, yA > 0, the exposure distance calculation formula is as follows:

[0062] The upper limit of lightning current integration, that is, the maximum shielding failure current is the current when the exposure distance Zs is zero.

[0063] In some embodiments, the four-condition exposure distance classification acquisition method includes the following specific steps: Based on the lightning current value, the strike distance formula recommended by authoritative organizations such as IEEE is adopted to determine the corresponding multiple strike distances as four conditions. The multiple strike distances include the strike distance of the lightning conductor, the strike distance of the conductor, and the strike distance of the ground. These strike distances form the basis of the electrical geometric model.

[0064] Based on the relative relationship between the strike distance and transmission line structural parameters, such as line-to-line distance, protection angle, and ground height, the geometric composition of the exposure distance is logically judged, thereby classifying the acquisition of the exposure distance and obtaining the classification result; the classification result determines the mathematical form of the exposure distance.

[0065] Based on the classification results, a corresponding formula is selected from multiple preset exposure distance formulas; these preset formulas correspond to different geometric scenarios, ensuring the universality and accuracy of the calculation.

[0066] Using the selected formula, the exposure distance corresponding to the lightning current value can be obtained. By numerically integrating the exposure distances under a series of lightning current values, the bypass tripping rate can be obtained based on the exposure distance. In this embodiment, the entire acquisition process achieves a precise conversion from microscopic geometric analysis to macroscopic probabilistic statistics.

[0067] As another embodiment of the present invention, the tripping rate can be calculated using MATLAB programming, see reference. Figure 3 The calculation process specifically includes: Step 1: Begin by inputting the structural parameters of each tower, the operating voltage of the transmission line, the lightning characteristic parameters, and the lightning current amplitude. I = I min +n× di , di Parameters such as iteration step size.

[0068] Step 2: n i = n i 1+1 n i = n i 1+1.

[0069] Step 3: Calculate the striking distance, exposure distance, and lightning current probability density under the current lightning current, and calculate the circuit breaker tripping rate. dn and the winding trip micro-element and n = n + dn .

[0070] Step 4: Determine Z s ≤0, otherwise return to step 2.

[0071] Step 5: If yes, output the lightning current amplitude, the inrush tripping micro-element, and the inrush tripping rate.

[0072] Step 6: End.

[0073] As another embodiment of the present invention, this embodiment provides a lightning protection configuration device for power transmission lines, see reference. Figure 5 The device includes the following functional modules: Simulation model acquisition module 421: Used to acquire a lightning transient simulation model of the transmission line, which is based on the electrical and structural parameters of the transmission line. Specifically, it includes: receiving the line's electrical parameters (voltage level, conductor type) and structural parameters (tower type, span) input by the user, automatically calling simulation software interfaces such as ATP-EMTP, and generating a lightning transient simulation model.

[0074] Lightning withstand level calculation module 422: Based on the lightning transient simulation model and the maximum lightning withstand value of the transmission line, it obtains backflash lightning withstand data and indirect lightning withstand data of the transmission line. Specifically, it allows users to set or import current-carrying parameters of the lightning protection device from the database, such as energy withstand value, and uses this as a criterion to automatically call the simulation model for batch calculation, outputting backflash and indirect lightning withstand level data tables under different configurations.

[0075] Trip rate calculation module 423: Used to obtain the corresponding backflash trip rate based on the backflash withstand data; and to obtain the corresponding backflash trip rate based on the backflash withstand data. Specifically, it includes a built-in calculation engine using the procedure method and the four-condition exposure distance method. After the user inputs the lightning withstand level data, the module automatically calls up data such as ground flash density and lightning current probability distribution to calculate the backflash, backflash, and total lightning trip rates for segments and the entire line.

[0076] Configuration determination module 424: Used to determine the lightning protection configuration of transmission lines by using the backflashover tripping rate and the bypass tripping rate as configuration indicators. Specifically, this module can be configured as an optimization algorithm interface. After the user inputs the target tripping rate, the module can automatically traverse different lightning protection device current parameters and installation schemes, calculate the corresponding total tripping rate and estimated cost, compare the tripping rate and cost under different lightning protection device current parameters, and display the "lightning protection effect-economic efficiency" relationship in the form of a list or curve to assist the user in decision-making. It generates the optimal lightning protection configuration parameter file, such as CAD drawings, material lists, and construction schemes, and finally generates an optimal lightning protection configuration scheme for transmission lines, including recommended device models and installation locations, and distributes it through the output interface.

[0077] In some embodiments, the internal structure of the trip rate calculation module is crucial for achieving accurate assessment. This module specifically includes two sub-modules: The backflashover tripping rate calculation submodule, upon receiving backflashover lightning withstand data, does not use it directly but instead performs secondary calculations using industry-recognized standard methods. This submodule automatically accesses external databases or user input to obtain empirical parameters such as lightning strike width, strike rate, and arc-building rate required for the calculation. These parameters can be referenced from research data in the literature. Simultaneously, it connects to a lightning location system to obtain the ground flash density and cumulative lightning current probability curves along the line corridor, ensuring that the calculation results closely match actual lightning activity.

[0078] The submodule for calculating the lightning strike trip rate employs a more refined electrical geometry model using the exposure distance method. This method assumes that lightning leader channels extend perpendicularly downwards from the ground, simplifying the complex physical process of lightning strikes into a calculable geometric problem. Its core is the definition of exposure distance, which is the horizontal distance between the intersection of the shielding arc and the exposure arc, and the intersection of the exposure arc and the ground strike distance line. The submodule's logic is: if the lightning leader falls within the exposure distance range, the conductor is struck; if the leader falls outside this range, the conductor is effectively shielded. Based on this, it uses the lightning withstand level as the lower limit of integration, integrating the exposure distance with the lightning current probability density function to obtain the final lightning strike trip rate.

[0079] In some embodiments, the configuration determination module is designed to include two functional units to handle the complexity of long-distance routes: The segmented processing and weighted calculation unit is the core for addressing line variations. In practical applications, further considering the differences in lightning strike characteristics across the entire transmission line—for example, the first 50 kilometers of the line might be in plains, and the next 50 kilometers in mountains—this unit first divides the entire line into "plain sections" and "mountain sections." Then, it calls the tripping rate calculation module to calculate the backflashover tripping rate and backflashover tripping rate for each of these two segments. Finally, it uses the line length of each segment as a weight and performs a weighted average to obtain the total lightning tripping rate of the transmission line. This method provides a more accurate reflection of the comprehensive lightning strike characteristics of the transmission line.

[0080] The configuration index generation unit then uses the aforementioned total rate for final decision-making. It sets this total lightning trip rate as the most critical configuration index and specifies its purpose as selecting the current-carrying parameters for surge arresters or surge protection insulators. For example, it assesses whether a surge arrester with a 100kA current-carrying capacity can reduce the total trip rate below the target value; if not, it automatically recommends a 150kA model and calculates its economic efficiency.

[0081] In some embodiments, to balance computational accuracy and efficiency, the simulation model acquisition module constructs a local transmission line simulation model of the lightning transient situation. Specifically, the module selects a typical continuous section from the entire line, generally establishing a local transmission line model with 9 to 11 towers. To eliminate the influence of model boundaries on the simulation results, the module automatically sets equivalent power sources and loads at both ends of this local model to simulate its connection to an infinitely long line.

[0082] In some embodiments, to improve simulation accuracy, the simulation model acquisition module performs a crucial step after constructing the local model: simulation processing of the local transmission line simulation model, where the line considers the impulse corona effect. This means that the module enables the corona simulation option in the simulation settings, which changes the dynamic capacitance parameters of the line, thereby more realistically simulating the attenuation and distortion of lightning overvoltage waves during propagation. Finally, the module outputs simulation results of the impulse corona effect including the corona effect, providing a more accurate data foundation for subsequent lightning withstand level calculations.

[0083] In this embodiment, the corona effect simulation function is implemented by a dedicated shock corona simulation submodule within the simulation model acquisition module. The workflow of this submodule is as follows: First, based on the simulated transmission line, each span of conductor in the model is divided into several small segments, and then an equivalent circuit is connected in parallel to each small segment.

[0084] Secondly, an equivalent analog circuit was obtained. This circuit was not designed arbitrarily, but rather obtained by connecting a diode, a voltage-controlled switch, and an additional capacitor in series. The diode ensures unidirectional current flow, the voltage-controlled switch simulates the corona initiation voltage, and the additional capacitor simulates the dynamic capacitance of the corona sleeve.

[0085] Finally, to determine the circuit parameters, based on the conductor geometry parameters of the simulated transmission line, such as conductor radius and number of splits, the impulse corona parameters, such as additional capacitance and switching action voltage, are calculated using theoretical formulas. After incorporating these parameterized circuits into the simulation model, simulation results of the impulse corona effect can be generated.

[0086] In this embodiment, the criteria for the lightning withstand level calculation module are clearly defined and engineered. During simulation, the criterion is that the lightning protection device absorbs energy up to its maximum withstand capacity. Specifically, during the simulation, the module calculates the integral of the square of the current flowing through the arrester over time in real time, i.e., the absorbed energy. Once this energy value reaches the maximum energy withstand value specified in the arrester's datasheet, the module immediately determines that a line fault has occurred under this lightning current and records the lightning current amplitude at this time as either backflashover lightning withstand data or side-flashover lightning withstand data.

[0087] In this embodiment, the tripping rate calculation submodule within the tripping rate calculation module employs a more refined and systematic method when executing the electrical geometry model. Specifically, this submodule is used to obtain the tripping rate using the electrical geometry model exposure distance method. When calculating the exposure distance, a four-condition-based classification method is proposed. This means that instead of using a fixed formula to calculate the exposure distance, logical judgment is first performed to classify the calculation scenario into different categories based on the line structure and lightning current magnitude. Then, the most suitable formula is selected from a preset formula library for calculation, thereby greatly improving the calculation accuracy and universality.

[0088] In this embodiment, the specific implementation steps of the four-condition exposure distance classification acquisition method in the bypass tripping rate calculation submodule are as follows: To determine the strike distance, this submodule first uses the lightning current value and calls the formula recommended by IEEE to calculate the corresponding strike distance of the lightning conductor, the strike distance of the conductor, and the strike distance of the ground.

[0089] After classification and judgment, it then performs a rigorous four-condition logic judgment based on the relative relationship between the strike distance and the transmission line structural parameters to determine the geometric shape under the current lightning current.

[0090] The four conditions are as follows: 1) The relationship between the distance d between the lightning protection wire and the conductor and the sum of the strike distances of the lightning protection wire and the conductor (rss+rsc) (Does intersection point A exist?) 2) The relationship between the horizontal distance dsinθ between the lightning protection wire and the conductor and the sum of the strike distances of the lightning protection wire and the conductor (rss+rsc) (the shielding effect of the shielded arc on the exposed arc in the horizontal direction). 3) The relationship between the ground strike distance rsg and the conductor height hsc (the relationship between the x-coordinate of the intersection point B, i.e., xB, and dsinθ+rsc); 4) The relationship between the ordinate of point A, yA, and 0 (the relationship between the abscissa of the intersection point A, xA, and rss).

[0091] Based on the combination of the above four conditions, the submodule selects a corresponding formula from multiple preset exposure distance acquisition formulas. Using the selected formula, the exposure distance corresponding to the lightning current value is obtained. Finally, the submodule substitutes the calculated exposure distance into the integral formula and obtains the bypass tripping rate based on the exposure distance.

[0092] Embodiments of this application also provide an electronic device, with reference to Figure 4It includes a memory 401 and a processor 402, the memory storing a computer program and the processor being configured to run the computer program to perform the steps in any of the above embodiments of the transmission line lightning protection configuration method.

[0093] Embodiments of this application also provide a computer-readable storage medium storing a computer program, wherein the computer program is configured to execute the steps in any of the above embodiments of the transmission line lightning protection configuration method when it is run.

[0094] In one exemplary embodiment, the aforementioned computer-readable storage medium may include, but is not limited to, various media capable of storing computer programs, such as a USB flash drive, read-only memory (ROM), random access memory (RAM), portable hard disk, magnetic disk, or optical disk.

[0095] The embodiments of this application also provide a computer program product, which includes a computer program that, when executed by a processor, implements the steps in any of the above embodiments of the transmission line lightning protection configuration method.

[0096] Embodiments of this application also provide another computer program product, including a non-volatile computer-readable storage medium storing a computer program, which, when executed by a processor, implements the steps in any of the above embodiments of the transmission line lightning protection configuration method.

[0097] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0098] The above description is merely a specific embodiment of the present invention, enabling those skilled in the art to understand or implement the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the present invention is not to be limited to the embodiments described herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for configuring lightning protection for transmission lines, characterized in that, include: A transient simulation model of lightning strikes on a transmission line is obtained, which is derived from the electrical and structural parameters of the transmission line. Based on the aforementioned lightning transient simulation model, and combined with the maximum lightning protection withstand value of the transmission line, backflashover lightning withstand data and swirlover lightning withstand data are obtained. Based on the lightning protection data, the corresponding lightning trip rate is obtained; Based on the backflashover resistance data, the corresponding backflashover trip rate is obtained; The backflashover trip rate and the backflashover trip rate are used as configuration indicators to generate the lightning protection configuration for transmission lines.

2. The method of claim 1, wherein The step of obtaining the corresponding backflashover trip rate and backflashover trip rate based on the backflashover resistance data and the backflashover resistance data includes: Based on backflashover lightning withstand data and lightning bypass lightning withstand data, the backflashover trip rate is obtained using the procedure method. Based on backflashover and lightning protection data, the lightning protection trip rate is obtained using the electrical geometry model exposure distance method.

3. The method of claim 1, wherein Using the backflashover tripping rate and the bypass tripping rate as configuration indicators, a lightning protection configuration for transmission lines is generated, including: Acquire segmented transmission lines; Based on the backflashover lightning withstand data and the backflashover lightning withstand data of the segmented transmission line, the backflashover trip rate and the backflashover trip rate of the segmented transmission line are obtained. The total lightning trip rate of the transmission line is obtained by weighted averaging of the backflash trip rate and the backflash trip rate of the segmented transmission line. The total lightning trip rate is used as the configuration index for the lightning protection configuration of the transmission line.

4. The method of claim 1, wherein The lightning strike transient simulation model is a local transmission line simulation model.

5. The method of claim 4, wherein Simulation results of the impact corona effect are obtained through simulation processing of the local transmission line simulation model.

6. The method of claim 5, wherein The method for obtaining the simulation results of the shock corona effect is as follows: Based on the simulated transmission line, several parallel segmented simulated transmission lines were obtained; An equivalent simulation circuit is obtained, and the impact corona of the segmented simulated transmission line is obtained using the equivalent simulation circuit; wherein, the equivalent simulation circuit is obtained by connecting a diode, a voltage-controlled switch and an additional capacitor in series; Based on the conductor geometric parameters of the segmented simulated transmission line, the impact corona parameters of the equivalent simulation circuit are obtained, and the simulation results of the impact corona effect are generated.

7. The method of claim 1, wherein Based on the aforementioned lightning transient simulation model, and combined with the maximum lightning withstand value of the transmission line, backflashover lightning withstand data and swirlover lightning withstand data are obtained, specifically as follows: Using the maximum lightning withstand value in the historical lightning protection configuration of the transmission line as the criterion, the backflash lightning withstand data and the backflash lightning withstand data of the transmission line are obtained.

8. The method of claim 2, wherein The method of obtaining the tripping rate using the electrical geometry model exposure distance method is based on a four-condition exposure distance classification method.

9. The method of claim 8, wherein The four-condition-based exposure distance classification acquisition method includes: Based on the lightning current value, multiple strike distances are determined as four conditions, including the strike distance of the lightning conductor, the strike distance of the conductor, and the strike distance of the ground. Based on the relative relationship between the strike distance and the structural parameters of the transmission line, the acquisition of exposure distance is classified, and the classification results are obtained. Based on the classification results, select a corresponding formula from multiple preset exposure distance acquisition formulas; Using the selected formula, the exposure distance corresponding to the lightning current value is obtained; The bypass tripping rate is obtained based on the exposure distance.

10. A lightning protection arrangement for a power transmission line, c h a r a c t e r i s e d in that include: The simulation model acquisition module is used to acquire the lightning transient simulation model of the transmission line. The lightning transient simulation model of the transmission line is obtained using the electrical and structural parameters of the transmission line. The lightning withstand level calculation module is used to obtain backflash lightning withstand data and swirl lightning withstand data based on the lightning transient simulation model and the maximum lightning withstand value of the transmission line. The tripping rate calculation module is used to obtain the corresponding tripping rate based on the lightning protection data and the corresponding backflashover tripping rate based on the lightning protection data. The configuration determination module is used to generate the lightning protection configuration for transmission lines by using the backflashover tripping rate and the backflashover tripping rate as configuration indicators.

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