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Wind turbines are considered one of the tallest buildings vulnerable to lightning strikes as they lack a protection system for large-scale carbon-fibre epoxy composite structures. Blades are more affected by lightning due to their large scale, which is the highest point in wind turbine structure. Knowledge of cloud-to-ground (CG) lightning, lightning protection system (LPS), electrical field relation and receptor configuration are explained. A design from an actual wind turbine blade is used to study the effect of lightning. The receptor plays an essential role in determining the efficiency of (LPS). To investigate the impact of receptors with different shapes and sizes, two different types of lightning protection receptors are used to perform their effect on lightning. Three different radius of lightning copper receptor disks, 0.1m, 0.2m and 0.4m, have been tested. A triangle with a head to the downside simulates the lightning terminal. This paper is aimed to study and analyze the most suitable lightning protection for wind turbine blades to suggest the best parameters for receptor type and size. The electromagnetic Finite Element Method simulation recommends the minimum and maximum electric field that builds up around receptors, which has been used to determine the correct size and forms of receptors. Results from the lighting strike Simulation 0.1m receptor gives the highest value of electrical field interception 56.3MV/m compared with larger size receptor 0.4m with 18.7MV/m. This research revealed the effectiveness of different types of lightning receptors and the effect of the receptor's radius, which will offer better protection to the wind turbine [ABSTRACT FROM AUTHOR]

Indonesia is a country with the highest lightning density in the world. Lightning strikes are the highest cause of failure in transmission lines which will interrupt the availability of electricity. PLN as an asset owner and manager of transmission lines wants to make sure the reliability of its assets from any disturbances. To minimize the impact of lightning strikes on the transmission line, PLN utilizes data from the lightning detection system installed since 2017 to support the planning and operational processes. To improve the performance of transmission lines against lightning strikes, several mitigation options are implemented in the field such as installation of separated ground wire on towers, installation of transmission lightning arresters, and installation of active air terminals. The performance of each options was known by comparing their successful rate in protecting the transmission line. Each options used gives varying results with an average successful rate above 96% as shown in this paper. [ABSTRACT FROM AUTHOR]

Lightning strikes on distribution lines can result in transient overvoltage. To overcome this problem, surge arresters is used as a lightning protection. This paper aims to explain the effect of arrester position on distribution transformers with respect to protection performance. Voltage drop along lead wire method was used in this analysis. This voltage drop occurs when the wire is passed through a lightning current and parallel to the equipment being protected. The total voltage occurs on the transformer is the sum of the arrester residual voltage and the total inductive voltage drop of the leads during the lightning stroke, thereby reducing the protective margin of the system. A simulation circuit modeled in ATP-EMTP software which presents a 20kV distribution feeder and arrester protection. The lead length modelled as inductance per meter. The results show the total voltage for 1-meter-long of lead length was about 45 kV, the total voltage of 2 meter was about 75 kV and 3meter lead length was 105 kV for lightning 20kA, 1.2/50 µs. [ABSTRACT FROM AUTHOR]

Exposure to adverse weather conditions is regarded as one of the most sensitive topics when it comes to wind turbines. The starting point of the inspection is defined by the procedure of establishing the facts regarding wind turbine's blades' surface and structural condition as well as the functionality of Lightning Protection System (LPS). Particular attention will be directed toward the problem of pitch and yaw control using wind turbine's control system (pitch1, yaw2) via specialized software used to test the current condition of the blades. A three-dimensional display using Cornis software package in combination with an electronically controlled rotating mechanical joint is used for the purpose of inspecting the actual condition of the blades. [ABSTRACT FROM AUTHOR]

The down conductor system is one of the essential components besides the air termination system and the earth termination system, since that the objective of this study is to investigate the effect of different type of down conductor materials on the varying angles of down conductors with different separation distances due to lightning strike. There were numerous materials of down conductor utilized worldwide in the Lightning Protection System (LPS) installation. In this circumstance, the aluminium and galvanized steel materials are taken into consideration to be resolved with reference to the electric field profile. The accomplished whole system of Lightning Protection System (LPS) for sheltered structure, is being modelled that abide by the standard of MS IEC 2007. Further, this entire system is modelled based on the outstanding of soil resistivity grounding parameter. Consequently, it is found that the galvanized steel material is more critical than aluminium in most angles due to the higher electric field intensity. [ABSTRACT FROM AUTHOR]

In this paper, a conceptual and practical approach for total lightning protection system based on the MS/IEC requirements on Ground-mounted Photovoltaic lightning protection system are discussed. The test site is located at the Renewable Energy Research Office (RERO) Faculty of Engineering UPM Serdang, Malaysia with installed capacity of 10 kWp Monocrystalline PV modules c/w Sun Grow Inverter/Data logging system. Lightning current which passes through the common lightning protection system may still dispersed and affect the ground-mounted PV power system mainly due to the uncertainties of point-of-strike. Hence the uniqueness of this project is the strategic structure bonding of PV systems with wind turbine (external pole) and perimeter fencing to achieve a good common earthing configuration. The protection system is also equipped with Surge Protection Devices (SPD) based on the zonal protection scheme to protect the site from both direct and indirect damages of lightning, with special attention to the protection of PV panels and inverters. [ABSTRACT FROM AUTHOR]

150 kV overhead transmission lines that span from Balambano, Larona and Karebbe Hydro Power Plants to nickel processing plant switchyard are located in a high lightning density area. Before EMTs installed in 2015, there were many complaints of damage to the tower insulators due to lightning strikes that caused total black out. The EMT installation was performed on selected towers at a location based on the mapping in an environment with high lightning density and based on historical location data of reported insulation damage. The selected towers are equipped with isolated lightning rod (early streamer), double shielded down conductor and magnetic tape current measurement system while other towers that have not yet been decided to be installed with EMT will be further evaluated. The engineering modification is to avoid the effect of back flash over and shielding failure of lightning strike that potentially damages the insulator and triggers ground fault. The transmission lines condition was observed due to their good performance after improvement of lightning protection system (LPS). The significant reduction of transmission line outages is reported. Analysis was performed on the existence of EMT that contributed to the failure reduction. Its presence provides protection against damage to high voltage tower insulators as indicated by the increasing value of MTTF. The failure rate is calculated to determine the reliability level of the EMT system which is then compared with the level of reliability without using the EMT system. This lightning protection equipment is reliable enough to avoid direct lightning strikes to the tower and wire lines and to prevent back flash over and shielding failure. The improvement reduces outages and increases the reliability significantly. [ABSTRACT FROM AUTHOR]

One of the most used source of energy in so-called "green power stations" are photovoltaic stations (PVS). They are the main type of installations for generating energy from the Sun. Due to the outdoor installation of the PVS equipment the forces of nature have influence on it and respectively there is a risk of some kind of rejections or even material losses. The landscape environment such as high hills, trees or ponds placed in dangerous proximity, often causes risk of direct or indirect lightning strikes during the storm weather. This paper overview the physical aspect in case of big lightning strike, considering the crucial factors which influence the process and gives a main approach for preventing or restriction the damages in that type of incidents. [ABSTRACT FROM AUTHOR]

Development of lightning protection standards for petrochemical processing and storage facilities has progressed significantly over the past 20 years. Standard requirements have become more stringent and prescriptive. Understanding of development and propagation of lightning has grown with the advent of 3- D detection systems. This is Part 1 of a 3-part primer on lightning protection systems for petrochemical production, storage, and processing facilities. Part 1 covers the basic science behind lightning strikes, and the history of lightning research, protection systems, and models of attachment. The purpose of this paper, and the primer series, is to update the design and operating engineer's knowledge of lightning protection at petrochemical facilities, and to increase the safety of these facilities to workers and equipment. [ABSTRACT FROM AUTHOR]

In January 2012, two highly endangered Mountain Bongo's were killed by lightning in the National Zoological Gardens of South Africa. These animals are on the critically endangered list and therefore as many risks should be mitigated where possible. Understanding and calculating the risk associated with lightning to animals within the enclosure is performed using IEC 62305-2 methods. In addition an alternate method is proposed looking at lightning current parameters and lightning ground flash data to determine a median lethal limit for a particular environment. From this a lethal area percentage for an outdoor environment can be determined. This is found to be approximately 75% for the enclosure. This would indicate that lightning protection measures should be put in place in order to prevent further losses as a result of lightning. [ABSTRACT FROM PUBLISHER]

The present paper aims to illustrate the influence of the main factors which affect the selection and installation of an SPD for the protection of electrical and electronic systems against overcurrent and overvoltage due to direct lightning flash to a structure. The two most typical SPDs are considered, namely switching and limiting type. Simple rules are established for the selection of effective SPD with regard to the discharge current, its protection level and location. [ABSTRACT FROM PUBLISHER]

A joint research project between AES Sul, the Federal University of Itajubá and the University of Bologna aims at defining the required protections against lightning-originated overvoltages in a resonant grounded distribution system in order to achieve the adequate lightning performance level with minimum cost. The paper aims at illustrating the effectiveness of the presence of a surge arrester or an arcing-horn gap and its protective zone by means of simulations obtained with a computer code for the calculation of lightning induced voltages that takes also into account the steady-state voltage. The results of a statistical analysis for a single multiconductor line are eventually presented and discussed. [ABSTRACT FROM PUBLISHER]

The present paper aims to provide insights for a better and simpler approach to risk assessment due to lightning. Reference is made to the documents recently issued in the frame of the International and European Standards. [ABSTRACT FROM PUBLISHER]

This paper focuses on design practices for the effective placement of downconductors to increase the level of direct lightning strike protection of Airport Traffic Control Towers (ATCT) in the United States. The adopted design practice is based on the use of the voltage gradient model as applied to tall towers. A scheme of balanced placement of downconductors for ATCTs is presented along with a simplified PSpice simulation that indicates related performance improvements. [ABSTRACT FROM PUBLISHER]

The efficiency of the blade lightning protection system depends to a great extend on the effectiveness of the receptor to intercept the lightning discharge. When the blade is exposed to a high electric field, streamers are mainly initiated from the receptor surface, but lightning attachment on the blade surface instead of the receptor is also possible, with the risk of damages in the composite structure as a consequence. The present paper focuses on electrical fields and streamer activity in connection to conductive components inside a wind turbine blade when a downward leader is approaching the wind turbine. High voltage tests have been carried out to study the development of streamers in conductive components inside a fiberglass structure, and the results have been correlated with the simulations of the electric field performed using Finite Element Method. Finally, potential applications of the results of this study are discussed. [ABSTRACT FROM PUBLISHER]

Photovoltaic power generating system (PVPGS) can be affected by direct and nearby flashes. In case of direct lightning, physical damage and failure of some apparatus can happen. Also the nearby lightning, by electromagnetic pulse (LEMP), can cause damages. An insufficient protection from lightning damages can increase the time of the return of investment (ROI) of the PV power generating system. The risk assessment is performed by taking into account the 2nd edition of IEC 62305-2, and the results are compared with those obtained by using the 1st edition. [ABSTRACT FROM PUBLISHER]

A new approach to the protection of electronics is considered to comply better with the requirements of lightning protection. Input power distribution in modal filter (MF) resistive terminations is analyzed. Dependencies of the MF power dissipation on the excitation pulse parameters have been obtained for 1-, 2-, 3-, 4-stage MF with fixed total length. Conclusions reveal potentially vulnerable parts which should be improved in order to prevent the MF failure due to overload of certain parts. [ABSTRACT FROM PUBLISHER]

The core objective of this study was to investigate the behavior of electric discharge exited in air over water and to study the way in which the lightning impulse is conducted into a water body. During the experiments, standard lightning impulses from −550 kV to 350 kV have been directed on water surfaces and surface discharges has been photographed using two cameras. The conductivity of the water has been varied from 41.5 µS/cm to 51.5 mS/cm. Analysis carried out in the study revealed that the current rather travels along the water surface than into the water when the conductivity of the water is low. A logarithmic variation was observed between the calculated electric field and the conductivity. For this variation a saturating trend could be observed and it appeared as if there is a critical value for the electric field below which no penetration will occur at any level of conductivity. Based on the experimental results of this study it can be estimated that to be less than 1.5×105 V/m for the positive breakdown and −5.0×105 V/m for the negative breakdown. [ABSTRACT FROM PUBLISHER]

A great number of onshore wind power plants are constructed and planned. And many large-scale offshore wind power plants are constructed and planned for the past some years. Almost large wind turbine blades have the receptor on the blade for the lightning protection, and down conductors are connected to receptor inside the blade. However, the wind turbine blades have been damaged by lightning. So, it is need to develop new lightning protection method for the blade with receptor. The authors thought that it is possible to lead the lightning discharge to the receptor smoothly on the blade by using the backside electrode. In addition, the authors also thought that it is easy to discharge on the blade when the surrounding seawater was sprayed on the blades of offshore wind turbine. The paper shows two experimental results. The lightning impulse discharge on the test model blade was found to lead to the receptor smoothly by using the backside electrode. However, other problem was emerged. The flashover voltage was decreased on a blade peace and glass fiber reinforced plastics (GFRP) board piece when the surfaces of the test pieces were sprayed with salty moisture. [ABSTRACT FROM PUBLISHER]

A new structure of modal filter which is more relevant for lightning protection of electronics than previously considered structures is proposed. Decrease of modal filter length or increase of original pulse width by factor of 10 and increase of modal filter attenuation from factor of 2 up to factor of 5 is shown. Condition for equal magnitudes of decomposed pulses and analytic formula for their values against a ratio of even to odd mode characteristic impedances are derived. Dependence of these values on coupling is shown for practical parameters of the new structure based on FR-4. On the basis of the calculated data an experimental prototype of an improved modal filter has been made. An experimental investigation has been performed. [ABSTRACT FROM PUBLISHER]

This paper proposes an alternative and simple methodology to find the transient voltage response of a ground electrode in the time-domain. The methodology uses a parametric modeling approach to obtain a model, in terms of a polynomial ratio, to represent the ground electrode impedance in the frequency-domain. Once this model is obtained, it is used to derive a time domain step response for the electrode impedance, which is further used in the procedure to derive the desired transient voltage response. The proposed approach deals with single wire ground electrodes and also with the typical arrangements used in transmission lines grounding towers, with several coupled electrodes. Comparisons with other methodology and with measured results are presented. An application example is used to demonstrate the proposed methodology usefulness. [ABSTRACT FROM PUBLISHER]

A comprehensive implementation of the risk management methodology detailed in the IEC 62305-2:2010 (Protection against lightning, Part 2: Risk management), called the Lightning Risk Assessment (LIRA) tool, is presented. LIRA was developed to facilitate the risk assessment calculations presented in IEC 62305-2 by means of a Graphical User Interface (GUI) that allows specifying all input parameters, in accordance with the definitions and values presented in the standard. The user has access to all the parameter values and calculation methods as detailed in the standard. This tool provides the capability to evaluate unlimited individual services in an unlimited number of zones in addition to a report generation capability that lists all input parameters and calculation results in several report formats. Furthermore, LIRA provides a direct interface to a Monte Carlo statistical tool, previously developed at the Kennedy Space Center (KSC), as an additional method of evaluating the annual number of dangerous events. The Hospital case study detailed in Annex E.4 of the standard is presented and final results from LIRA are compared to those in the standard. A case study of a typical Florida household is also presented using the Monte Carlo statistical tool as the input source of the annual number of dangerous events. [ABSTRACT FROM PUBLISHER]

A new Lightning Protection System (LPS) was designed and built at Launch Complex 39B (LC39B), at the Kennedy Space Center (KSC), Florida, which consists of a catenary wire system (at a height of about 181 meters above ground level) supported by three insulators installed atop three towers in a triangular configuration. Nine downconductors (each about 250 meters long) are connected to the catenary wire system. Each downconductor is connected to a 7.62-meter-radius circular counterpoise conductor with six equally spaced, 6-meter-long vertical grounding rods. Grounding requirements at LC39B call for all underground and aboveground metallic piping, enclosures, raceways, and cable trays, within 7.62 meters of the counterpoise, to be bonded to the counterpoise, which results in a complex interconnected grounding system, given the many metallic piping, raceways, and cable trays that run in multiple directions around LC39B. The complexity of this grounding system makes the fall-of-potential method, which uses multiple metallic rods or stakes, unsuitable for measuring the grounding impedances of the downconductors. To calculate the grounding impedance of the downconductors, an Earth Ground Clamp (EGC), a stakeless device for measuring grounding impedance, and an Alternative Transient Program (ATP) model of the LPS are used. The EGC is used to measure the loop impedance plus the grounding impedance of each downconductor, and the ATP model is used to calculate the loop impedance of each downconductor circuit. The grounding resistance of the downconductors is then calculated by subtracting the ATP-calculated loop impedances from the EGC measurements. [ABSTRACT FROM PUBLISHER]

A new comprehensive lightning instrumentation system has been designed for Launch Complex 39B (LC39B) at the Kennedy Space Center (KSC), Florida. This new instrumentation system includes seven synchronized high-speed video cameras, current sensors installed on the nine downconductors of the new LC39B lightning protection system (LPS); four dH/dt, 3-axis measurement stations; and five dE/dt stations composed of two sensors each. The LPS received 8 direct lightning strikes (a total of 19 strokes) from March 31 through December 31 2011. The measured peak currents and locations are compared to those reported by the Cloud-to-Ground Lightning Surveillance System (CGLSS II) and the National Lightning Detection Network (NLDN). Results of comparison are presented and analyzed in this paper. [ABSTRACT FROM PUBLISHER]

This paper presents a new approach to evaluate the efficiency of surge protective devices (SPD) for the protection against lighting as applied on the electrical power systems of wind turbine generators (WTG). The parameters of the performance of the SPDs which are considered to be critical for this application are their lifetime and voltage protection level at the power input point of the equipment. In this paper a method is presented to determine the lifetime of a SPD component based on the estimation of its exposure to currents due to direct lightning on the WTG over its lifetime using a statistical analysis of the lightning currents that could strike on a WTG and a distribution analysis of the lightning current in the WTG's electrical and grounding system. A lifetime test procedure for SPDs is suggested followed by an experimental verification test. Moreover, the voltage protection level at the equipment power input point is considered and a test procedure is also proposed to measure the effective voltage protection level using several expected voltage and current waveforms. Experimental results are presented to demonstrate the dependence of the voltage protection level on the SPD technology, installation configuration and equipment input impedance. The same approach could also be used in other application areas of SPDs, provided that the corresponding test procedures are adapted to the specific requirements of each application. [ABSTRACT FROM PUBLISHER]

The effect of structure height on the lightning striking distance is estimated using a lightning strike model that takes into account the effect of connecting leaders. According to the results, the lightning striking distance may differ significantly from the values assumed in the IEC standard for structure heights beyond 30 m. However, for structure heights smaller than about 30 m, the results show that the values assumed by IEC do not differ significantly from the model's predictions based on a striking model taking into account the effect of connecting leaders. However, since IEC assumes a smaller striking distance than the ones predicted by the adopted model one can conclude that the safety is not compromised in adhering to the IEC standard. In this respect, further analysis making use of lightning strike models developed by other authors is recommended. [ABSTRACT FROM PUBLISHER]

Earth resistance of buried steel cages, encased in bentonite mixed concrete has been investigated. A reference pit was constructed with steel cage encasing in ordinary concrete. The land mass of the site has somewhat uniform surface soil resistivity which is in the range of 100 Ωm. The performance of earth resistance in each electrode has been measured for five months. The results show that for the first month, the lowest earth resistance and the highest decrement in earth resistance are shown by the pit with concrete having 20% bentonite. However, for the following four months, pits with bentonite mixed concrete showed increased earth resistance compared to the reference pit. These results indicate that the long-term reduction in earth resistance in electrodes encased with bentonite, as observed in previous studies, is not the case with electrodes embedded in bentonite mixed concrete. The initial reduction of earth resistance observed at pits with bentonite mixed concrete may most probably be due to the presence of hydrated bentonite which is not mixed with other constituents of concrete. Other than the pits with 20% and 70% bentonite, the outcome of this research thus far reaffirms the capability of concrete blocks to maintain earth resistance with small fluctuation. [ABSTRACT FROM PUBLISHER]

Grounding issues related to lightning currents have been addressed giving special attention to recommended practices in IEC 62305 (2010). Unambiguous recommendations are needed for the requirement of type A system or type B system or both systems for a given installation. Specifications of the length of conductors, based on the level of protection, were critically analyzed emphasizing the human risk related issues. Calculations reveal that at Level III and IV, the specified lengths of type A conductors may give step potentials, especially in highly resistive soils that may drive currents through human beings in the vicinity, exceeding lethal energy. Furthermore, specification of the limiting value of resistance for transient grounding systems may lead to hazardous situations as the difference between frequency dependent impedance and low frequency resistance may increase to very high values at Mega Hertz range where lightning energy spectrum has significant amplitude. Covering of a sizable surface area surrounding the grounding conductors with insulation material, is recommended as a practical solution to this issue. [ABSTRACT FROM PUBLISHER]

Results of the experimental investigations and physical simulation of the processes of lightning affection of the compacted and extended objects on models and the investigation of its lightning protection effectiveness using artificial charged aerosol clouds are presented. Peculiarities of affection of the grounded objects by the discharges from artificial charged aerosol clouds are presented and analyzed. Influence of the characteristics of lightning rod and object models (or lightning conductor and phase wire models) on the process of their affection by the discharge from charged aerosol has been analyzed. Comparison of the experimental results with the calculated and experimental methods of determination of the compacted and extended object lightning protection (in context of power objects) has been fulfilled. Recommendations on the improvement of lightning protection of the existing and projecting power energy objects have been proposed. [ABSTRACT FROM PUBLISHER]

Using of experimental methods for investigation of lightning and lightning protection physics was and is relevant as its help to build or approve the physical and mathematical models of thunderstorm and lightning discharge formation, to check and to analyze detail the possible effectiveness of modern and perspective methods and utilities of lighting protection. Application of artificial strongly charged aerosol clouds opens new possibilities for experimental simulation of the processes in thunderstorm clouds and lightning discharges, significantly approximates the physical simulation of process of object lightning affection to real thunderstorm situation. Paper presents the results of the using of artificial clouds of charged water aerosol for investigations of lightning and lightning protection physics. [ABSTRACT FROM PUBLISHER]

Lightning damage to facilities inside or in the vicinity of wind turbines becomes remarkably common. Most of the breakdowns and malfunctions of the electrical and control systems inside or in the vicinity of wind turbines are caused by ground potential rise due to lightning current flowing into the grounding system of the turbine. To clarify the transient characteristics of the wind turbine grounding systems and to understand the mechanism of the breakdowns and malfunctions, we have carried out field tests. In this paper, the measurements of transient grounding characteristics carried out at wind turbines are descried. [ABSTRACT FROM PUBLISHER]

The paper provides an overview on the past research activities and summarizes the main results on the study aimed at design and implementation of an online method for diagnostics of shielding effectiveness for real conductive shields. The review starts with the results of theoretical investigations on shielding electromagnetic fields with structurally irregular low permeability enclosures in quasi-statics and resonant modes. Then we address the motivation for and list the main features of a novel hybrid simulation method we designed for quasi-statics. Inspired by the theoretical advances and promising experimental results, we propose the prototype method for online diagnostics of shielding effectiveness of electromagnetic enclosures. Finally, we discuss the means and approaches for practical implementation of the proposed method in an intellectual self-diagnostic system. [ABSTRACT FROM PUBLISHER]

In this paper, the outline of countermeasures to enhance lightning-proof characteristics of traction power supply system in Tokyo metropolitan area which have been invested since 2009 is shown. Especially, the investment to improve grounding conductor in DC traction substations is advanced achievement which improve grounding system characteristics against surge voltage and current and explained in detail. The effects of the improvement constructions are also shown. [ABSTRACT FROM PUBLISHER]

Designing the lightning protection system could be simplified with classification the structure according to danger that determines the required degree of components of the LPS. This could be corrected on the base of result obtained by risk assessment in the case of important structures. [ABSTRACT FROM PUBLISHER]

Calculating shielding failure flashover rate of transmission line with regulation method, EGM method and LPM method, the height of conductor and ground wire are often expressed by average height, the terrain feature are often expressed by ground obliquity. If the actual line parameters are beyond the scope of the effective calculation conditions, traditional methods can't reflect the influence of sag and line corridor's complex terrain area. In recent years, some scholars put forward to select multiple tangent planes of a line span, then calculated the shielding failure flashover rates of every tangent planes to reflect the line span's lightning protection performance, but it was complicated to get the ground obliquities of every tangent planes. A new approach for calculating shielding failure flashover times in complex terrain area was presented, which was based on the electro-geometric model (EGM), the new method considered of the line corridor's micro-topography and the relative position among the ground wire, the conductor wire and the ground, a line span was taken as the research object, got the shielding failure flashover times of the line span through calculating the conductor exposed surface's horizontally-projected area. A 500kV transmission line in complex terrain area was taken as an example, the calculation results shown that using this method can obtain a line span's lightning protection performance simple and exactly, and reflect the influence of line corridor's complex terrain area better, which also provide a reference for differentiation technology and strategy of lightning protection. [ABSTRACT FROM PUBLISHER]

The central goal of lightning protection to power lines is to determine whether the device can meet the requirements under current environment with fixed parameters in geography, weather and the device itself. This paper presents models of regional distributions of ground flash densities with different geographical environments, models of thunderstorm day statistics based on the time periods and statistical models of intensity distribution of lightning currents. A model of decision-making supporting for lightning protection is made based on multidimensional decision analysis. Through the design of software platform for validation, the model and its technical method have been proved satisfying the requirements of lightning early warning of lines and the parameters of lightning protection when designing the lines. [ABSTRACT FROM PUBLISHER]

The use of rubber materials in wind turbine blades, for example in controllable trailing edge flaps, requires research on their behavior under heavy exposure to electric fields and electrical discharges. Since the complex construction of blades usually involves several and often inhomogeneous materials, the testing methods selected should reflect the realistic conditions. In this paper the applicability of rubber materials to thunderstorm environments is studied by performing electric breakdown tests and tracking resistance tests on selected samples, and the findings are related to the possible future application of rubber materials to wind turbine blades. [ABSTRACT FROM PUBLISHER]

As the largest archipelago in the world situated along equatorial line, Indonesia exposes to high potential lightning strikes, which are hazardous for operation of geothermal power plants. The severe effect of lightning strikes results in system malfunction leading to interrupted plant operation. This paper presents a novel grounding technique based on skin-effect theory and its implementation for protecting geothermal power plants from disruptive lightning strike effect. The corrosive condition of geothermal area is taken into consideration in design. The proposed technique was proven through the failure-free protected system during period of relative high lightning activity. [ABSTRACT FROM PUBLISHER]

The paper intends to give a contribution to the investigation on the expected surge current, peak value and shape, due to lightning electromagnetic impulse (LEMP) by flashes to the structure for the surge protective device (SPD) proper selection in order to assure electronic apparatus operation. The obtained results are discussed with the SPD requirements of international standard [1]. [ABSTRACT FROM PUBLISHER]

According to the lightning protection requirements of the facilities and equipments in oil depot, this paper proposes the integrated mobile lightning protection device and technology to protect lightning strike in different regions of oil depot, analyses the systemic composition and the technical characteristics of the integrated mobile lightning protection device and technology, and practically applies them to establish the lightning protection system in the important region of oil depot. The application shows that the integrated mobile lightning protection device and technology are safe, reliable, practical and convenient, which makes it suitable for widely applications. [ABSTRACT FROM PUBLISHER]

The lightning performance of overhead transmission lines is affected by many factors. Most of those factors are nature driven and are not predictable or controllable. Of those controllable factors affecting a line's lightning performance, the one that can be dealt with most cost-effectively is the transmission line's shielding. However, at some utilities, the design and selection of the line shielding method for transmission and sub-transmission lines operating at nominal voltages between 46 kV and 230 kV is typically relegated to a secondary level of importance because of the complexity of the calculations involved and an inherent reluctance to change. This paper presents a simplified method for optimizing the transmission line shielding angle to minimize the line's predicted lightning performance. The proposed method for optimizing the line's shielding angle relies on known formulas and procedures developed over the past four decades. The simplified method presented can be used by utilities in upgrading their current line shielding practices. [ABSTRACT FROM PUBLISHER]

Indonesia is situated at region with relative high keraunic level in the world. It is often reported that a lot of energy exploration companies in the region suffer from interference effects of the tropical atmospheric electricity as false alarm in companies' instrumentation system leading to malfunction. This paper presents an integrated framework of lightning protection system for instrumentation systems of geothermal power plant. The proposed framework is based on electromagnetic compatibility (EMC) and derived from our best practice in the field, which is proven as failure-free during period of relative high lightning activity. [ABSTRACT FROM PUBLISHER]

Lightning trip-out rate of catenary is high in China. It seriously affects the reliability of the traction power supply system. Electro-geometric model of catenary is built to evaluate the lightning failure performance of catenary in this paper. The formula on lightning scope of earth, return lines and catenary is deduced respectively. Furthermore, lightning strike probabilities of return lines and catenary wire are obtained, the trip-out numbers of induction lightning and direct lightning of 100 kilometers lines are calculated. At last, with the combination of calculation formula on the lightning current amplitude distribution and arc establishing rate recommended by DL / T620-1997, the total lightning trip-out rate and the proportion of a variety of lightning types are obtained. [ABSTRACT FROM PUBLISHER]

In this paper, based on Visual C + +6.0 high-level programming language, it developed the transmission line lightning trip evaluation system, this system could complete differential Lightning protection calculation, evaluate the transmission line's lightning performance and provide factor graphs of the lightning withstand level, with it user can take appropriate measures for lightning protection. In this paper, it selected a actual transmission line of Shenyang Power Supply Company to calculate, the result proved this system can be applied in transmission line lightning protection calculation in actual power system. [ABSTRACT FROM PUBLISHER]