Lightning Protection Measures Research Articles

Research on Lightning Protection Measures of MW Broadcasting Stations

Research on Lightning Protection Measures of MW Broadcasting Stations

Analysis of Lightning Fault of Railway 10kV Power Line and Application of Lightning Protection Measures

Analysis of Lightning Fault of Railway 10kV Power Line and Application of Lightning Protection Measures

Simulation and Experimental Analysis of Multi-Chamber Arc-Quenching Arresters (MCAA) for 10 kV Transmission Lines

Since conventional lightning protection measures do not effectively extinguish subsequent arcs of electrical frequency after the passage of lightning, it is impossible to prevent lightning-related accidents on the distribution lines. To solve this problem, a 10 kV multi-chamber arc-quenching arrester (MCAA) applicable to transmission lines of different voltage levels is developed. In order to research the arc-quenching characteristics of the MCAA, COMSOL software was used to simulate and analyze the high-speed airflow coupled arc process. Under the action of a strong airflow at high speed, the arc is segmented, the temperature of the arc falls sharply, and eventually, the arc is extinguished. In the simulation process, the conductivity of the arc and the clouds of change of air speed were achieved. It may be concluded that arc segmentation time and airflow generation time are at a subtle level. Meanwhile, an experimental circuit was established to conduct the arc-quenching experiment. A high-speed camera was used to observe the experimental process and the oscilloscope was used to record the arc-quenching waveform. The experimental results show that the MCAA had a good arc-extinguishing effect and that the arc was extinguished within 0.35 ms. The current amplitude of the frequency arc was 1.2 kA.

Selected Issues of Safe Operation of the Railway Traffic Control System in the Event of Exposition to Damage Caused by Lightning Discharges

Lightning discharge becomes a serious source of interference and damage for electronic and electrical power systems. Safe and reliable operation of railway traffic control systems requires proper protection against the effects of lightning. However, the current standards on lightning protection, PN-EN/EN/IEC 62305, do not cover railway objects. Moreover, there are no other standards or recommendations dedicated to the railway. The paper is an attempt to apply the procedure of lightning risk management according to PN-EN 62305-2 to select the proper protection measures in railway objects. A case study for the signal box with installed relaying and digital stations of the railway traffic control system is analyzed. The analysis comprises calculations based on the current standard PN-EN 62305-2:2012 but including the issues specific to railway traffic control. The risks of lightning losses have been calculated for two cases: without lightning protection measures and with protection measures proposed to decrease the risks below the tolerable values. The results show that a practically effective solution to reduce the risks is applying surge protective devices with proper characteristics. Another way is replacing unshielded incoming lines with shielded ones of given shield bonding way, and supplementing it with surge protective devices when necessary.

A Reliability-based Optimization Model for Comprehensive Lightning Protection System Design

Lightning strike is the main reason for the failure of overhead lines in distribution network, which seriously affects the reliability of power supply and power quality. The existing optimization research of lightning protection system(LPS) mainly focuses on a specific lightning protection method, and there are few kinds of research on comprehensive optimization methods among various lightning protection solutions. A model based on distribution network reliability index is proposed in this paper. In the model, mixed integer linear programming (MILP) is used to optimize the lightning protection measures of lightning rods, lightning wires and lightning arresters with different densities. The model considers the influence of arc over rate on the basis of related research and obtains a comprehensive optimization method of different protection measures acting on distribution lines. Taking an actual distribution network as an example, this paper applies the optimization model established to obtain the appropriate lightning protection measures for each line.

Analysis of the spatial-temporal distribution of lightning discharges in the North Caucasus

The organization of lightning protection measures is based on information about the nature of the distribution of lightning discharges, their number and the current value in the region of the location of the protection objects. Therefore, the most relevant direction of the study is to clarify the existing recommendations in the field of lightning protection. In the article, based on the data of long-term measurements of the LS 8000 lightning direction finding system located in the North Caucasus, the analysis of the registration of lightning parameters is carried out. The revealed regularities of the distribution of lightning discharges over the territory in different periods of the year are the basis for the approximation equations developed by the authors, which are used to describe the space-time density of lightning. Maps of the distribution of the number of lightning discharges per square kilometer obtained from the initial data and constructed according to the developed equations are presented, and the relevance of the results obtained is evaluated.

Lightning Current Simulation of 66-kV Substation With Power Cables Using the Three-Dimensional FDTD Method

Lightning currents may cause damage to power equipment in a substation and a transmission line (TL), and thus, to protect power equipment properly, it is required to install effective lightning protection measures on the basis of the prediction of electromagnetic transient phenomena through numerical simulations. In this article, using an electromagnetic transient simulation code developed on the basis of the 3-D finite-difference time-domain (FDTD) method, we simulate a 66-kV TL, 66-kV substation, and 6.6-kV distribution line, and carried out FDTD simulations by modeling a direct lightning strike to the TL tower. First, we study the effect of the lightning current waveform on the lightning currents flowing through the sheath voltage limiters (SVLs) of the power cables installed between the cable sheath and the tower structure and the lightning current flowing out of the substation into the distribution line through a surge arrester (SA) installed between the grounding structure of the substation and the distribution line. Second, we propose a technique for taking into account the influence of the lightning current flowing into the other TL towers via the shield wire for a long-duration lightning current, and we evaluate the effectiveness of some countermeasures to reduce the lightning currents flowing through the SVLs and SA.

Study on the Causes of Rural Lightning Disaster and Countermeasures of Lightning Protection and Disaster Reduction

With the development of the time and the progress of economy, great changes have taken place in the environment. In recent years, it is common to see bad weather, such as hurricane, drought, lightning and so on. The emergence of these weather has the greatest impact on farmers and crops, especially the lightning weather, not only that, but also sometimes cause personal injury. In face of the frequent occurrence of bad weather in recent years and its harm and threat to China's agriculture, rural areas, personnel, etc., the author makes a detailed study on the causes of rural lightning weather, analyzes the lightning protection measures in rural areas and their shortcomings, and summarizes the relevant improvement measures.

Research on Lightning Hazard and Lightning Protection Measures of Railway Substation

Research on Lightning Hazard and Lightning Protection Measures of Railway Substation

Simulation Research on Lightning Protection Effect of Distribution Line Lightning Protection Measures

Due to the low insulation level of distribution lines, the electromagnetic transient characteristics of lightning strikes are quite different from those of high-voltage transmission lines; the lightning protection measures used in high-voltage lines cannot be well applied to distribution lines. In order to further understand the various lightning protection measures and the effect of lightning protection measures on the improvement of the lightning resistance level of distribution lines, this paper evaluates the working principles, characteristics, lightning protection effects and existing deficiencies of various lightning protection measures used in distribution lines And using ATP-EMTP software to analyze several kinds of lightning protection measures commonly used in 10kV distribution lines, it has certain reference value for the selection of lightning protection measures of 10kV distribution lines.

Technical Analysis of Grid Connection of High-speed Railway Power Through Lines

For the power communication system of the high-speed railway, the power through line is the core power supply line, and its operation effect has a vital effect on the safety and stability of the high-speed railway operation. However, because the power penetrating line is largely restricted by the power system, and the lightning protection measures and insulation level are relatively weak, the grid connection is also very difficult. In order to realize the effective grid connection of high-speed railway power through-line, this paper analyzes its grid connection technology. In this analysis, it first analyzes the overall overview of the high-speed rail power penetration system; then it analyzes the specific principles of grid connection of the high-speed rail power penetration line; Finally, the simulation calculation and analysis of the specific grid connection are carried out. It is hoped that this analysis can provide sufficient technical support for the grid connection of the high-speed rail power through-line, so as to improve its application effect and safety.

Certification of Radome Lightning Direct Effects Protection

Composite material is used more and more in airplanes year after year. The electrical conductivity of composite material structure is poorer than metal structure, so appropriate lightning protection measures should be adopted to shunt lightning current when composite structure suffering lightning strike, and the harmful consequence will be minimized. The paper takes radome as an example, which is located at nose area liable to suffer lightning strike, introduces radome lightning protection measures, and according to lightning direct effect verification process, discusses on means of compliance, plans high voltage strike attachment test and high current physical damage test of radome. It provides reference for airworthiness verification for radome.

500 kV同塔双回交流输电线路绕击耐雷性能及防雷措施研究

500 kV同塔双回交流输电线路绕击耐雷性能及防雷措施研究

Study on electromagnetic environment analysis and lightning protection in buildings

When a direct strike occurs, the lightning surge current will intrude into the steel frame and steel bar of the building, forming a high lightning electromagnetic environment inside the building, which will affect the telecommunications equipment set in the building. Therefore, the problem of lightning protection in buildings becomes more and more important. In this paper, by studying the distribution law of lightning electromagnetic field in buildings, the intensity of magnetic field generated in buildings under different lightning strikes is analyzed. According to the three-dimensional diagram and equivalent diagram of the intensity of lightning magnetic field in each case, when the building encounters direct lightning, the lightning electromagnetic field is the strongest near the leadoff line, and the middle zone is weak. The lightning protection measures inside the building are put forward.

Система заземления для наземных ветроустановок.

The earth-termination system for towers of ground-based wind turbines in addition to protective and functional grounding provides lightning protection grounding, which is especially important since the wind turbine is susceptible to lightning strikes. If insufficient protective measures are taken, the risk of damage to a wind turbine due to a lightning strike increases. Therefore, a well-thought-out built-in grounding system for wind turbine towers is needed, which would function as necessary and guarantee long-term mechanical strength and corrosion resistance. The configuration of grounding systems for wind turbines is discussed in IEC 61400-24, which deals with the topic of lightning protection for wind turbines, including detailed information on the choice of lightning protection measures and surge protection. It is advisable to create a lightning protection concept at the initial stage of planning a wind turbine in order to avoid later costly repairs and retrofitting.

The Simulation Analysis of Factors Affecting Lightning Withstand Level of the Distribution Lines in Oilfield

Simulation analysis is an important method to study the lightning withstand level of distribution lines and conduct the design of line lightning protection. In the process of simulation, the components of the overhead line and the selection of the specific model of lightning current should be taken into account. All the work can be used to get the simulation results which are more consistent with the actual results. Based on the investigating the parameters of oil field lines, insulators and earth resistances, a lightning protection simulation model for typical distribution lines in oil field is built by using ATP-EMTP electromagnetic transient analysis program. By simulation analysis, the influence of line insulation level, earth resistance, layout parameters of arrests and lightning conductor on the lightning withstand level are studied. The results provide a scientific basis for the proposing of the comprehensive lightning protection measures of the distribution lines in oil field.

Lightning Surge Analysis of a Transmission Line Tower With an XLPE Power Cable and Metallic Cleats Using the FDTD Method

A direct lightning strike to a transmission line tower may cause overvoltages and insulation failures, and to avoid unexpected insulation failures and protect power equipment, it is necessary to install effective lightning protection measures. To design effective countermeasures, the prediction of lightning surge phenomena is required. The finite-difference time-domain (FDTD) method, one of the full-wave numerical approaches, which do not require the assumption of the transversal electromagnetic mode, has been an effective tool for predicting electromagnetic transient phenomena in 3-D structures, such as transmission line towers. In this article, using a technique for representing coaxial cables in the FDTD method, we simulate a reduced-scale model of a transmission line tower with a power cable, calculate the surge phenomena in the tower model when a surge current is injected into the top of the tower, and compare the FDTD results with the measured results for validation. Furthermore, we propose a technique for simulating the influence of using metallic cleats to fix a power cable to a transmission line tower for FDTD simulations in a 3-D arrangement, and we calculate surge phenomena in practical cross-linked polyethylene power cables placed over a ground plane and installed in a real-scale 77 kV transmission line tower. The FDTD results are validated through the comparison with measured results obtained in a previous study.

Research on the Lightning Intruding Overvoltage and Protection Measures of 500 kV AC Fault Current Limiter

As one of the key technologies to solve the problem of high short-circuit current, the fault current limiter (FCL) has become a research hotspot in China and abroad. The overvoltage and protection measures of the FCL are the key technologies for its application. Therefore, this paper studies the lightning intruding overvoltage and protection measures for a 500 kV FCL based on a high coupled split reactor (HCSR). Firstly, according to the main topology of the system and the 500 kV HCSR-FCL structure, the lightning intruding overvoltage simulation model of the 500 kV station, including the nearby transmission lines, is established on the PSCAD (Power Systems Computer Aided Design) program. Secondly, the lightning overvoltage of the equipment in the station and the components of the HCSR-FCL are simulated and analyzed when the transmission lines nearby are subjected to lightning shielding failure and back flashover. Meanwhile, the influence of the HCSR-FCL on the lightning overvoltage of the equipment in the station are compared and analyzed before and after the HCSR-FCL is installed. The simulation results show that the overvoltage of the equipment in the station and the components of the HCSR-FCL is more serious when the shielding failure occurs in the transmission lines nearby. The HCSR-FCL can reduce the lightning overvoltage of the equipment in the station, but the maximum inter-terminal and inter-arm lightning overvoltage of the HCSR can reach 1064 kV and 790 kV, respectively, under the current limiting state and the current sharing state. Finally, methods of increasing the arresters on the transmission lines side of the HCSR-FCL and shunt capacitor between each module of the HCSR-FCL are proposed to reduce the lightning overvoltage. The lightning impulse withstand voltage of each component of the HCSR is also proposed: The inter-terminal lightning impulse withstand voltage of HCSR is 170 kV. The inter-arm lightning impulse withstand voltage of HCSR is 200 kV. The terminal-to-ground lightning impulse withstand voltage of the HCSR-FCL is 1550 kV.

Lightning Protection Measurements for Solar Water Heaters

It is aiming at safety of the current situation of lightning protection from the hazards of solar water heaters. From the structure and working principle of solar water heaters and the way of lightning introduction, the paper discussed the protection measurements of direct lightning and inductive lightning, as well as shielding and equipotential bonding methods. These measurements can effectively reduce and avoid the occurrence of lightning strikes, and provide a comprehensive lightning protection construction method for installing solar water heaters. According to the number of water heaters and the way of laying, the lightning rod or lightning protection belt can be flexibly used for protection. While using lightning rods or lightning protection belts for lightning protection, it is also necessary to consider equipotential bonding by means of lightning protection facilities of buildings. This can be easy to install and cost-effective. In the design and construction of buildings, if the above measures can be considered, the safety hazards of solar water heaters can be effectively reduced, and the problems caused by the subsequent lightning protection measures can be reduced.

Lightning Faults Analysis and Protection Measures for UHV DC Transmission Line

Lightning Faults Analysis and Protection Measures for UHV DC Transmission Line