Rolling Sphere Method Research Articles

Lightning Strike Danger Zone Detector System Integrated with Smartphone

The potential for direct hits and bounces from buildings during thunderstorms can endanger pedestrians in the open area of the Faculty of Engineering Untirta campus. So far, there has been no danger warning in the open area so that pedestrians in the area are not prepared if unwanted things happen, especially when there is rain and lightning. Direct lightning strikes are one of the hydrometeorological events that need to be watched out for. Because of its impact that can cause damage to objects and casualties if exposed to humans. The campus area has a fairly large open area, making the threat of lightning strikes can occur at any time, especially during the rainy season. The purpose of this research is to design and implement a direct lightning strike hazard zone detection device in the campus area of the Faculty of Engineering UNTIRTA located in the city of Cilegon. The stages of research carried out include analyzing the open area of the FT campus using the Rolling sphere method. After that, plotting the area of the analysis results. Then an area detection tool was created which is categorized as a direct lightning strike danger zone that is integrated with Smartphone notifications.

Integration of electromagnetic and mechanical models for effective lightning protection in buildings

The study focused on the design of an advanced algorithm for the optimal sizing of protection systems against atmospheric discharges in architectural structures, applying the rolling sphere method. This technique facilitated the incorporation of user-specified parameters through an advanced graphical interface. The methodology began with the exhaustive accumulation of data relevant to the project. Risk indices were estimated through sophisticated risk analysis software applications. If adjustments were required, the process continued; If not, the building was considered to be adequately secured. The ground resistivity was evaluated according to IEEE Std. 81, and the rolling sphere method was implemented according to IEC 662305-3. The grounding systems were configured in accordance with IEEE Std. 142 and IEEE Std. 80. To analyze the interaction of electrical discharges with the protected building, the electrical equivalents of elements such as meshes, fused copper rods were computed. , and conductors positioned horizontally and vertically. Using these data, a model was built in ATPDraw, interconnected with Python for the generation of graphical representations of the current waves in the different protection subsystems. To conclude and corroborate the effectiveness of the process, the risk indices were reevaluated. The validation of the algorithm was achieved by minimizing the margin of error to insignificant levels by incorporating standardized data proposed by organizations such as IEC and IEEE, thus confirming the precision of the designed algorithm

Fenomena Back Flashover Akibat Sambaran Petir Pada SUTT 150 kV Haurgeulis–Sukamandi#2

Lightning disturbances on the 150 kV High Voltage Overhead Transmission Line (SUTT) Haurgeulis-Sukamandi #2 were analyzed to understand their causes and impacts. This study aims to identify and analyze lightning-induced disturbances using data from Fault Locator, Digital Fault Recorder, and Lightning Detection System. The methods used include calculating the protection angle, analyzing the maximum current before shield failure, and applying the Rolling Sphere method. The analysis results showed that the lightning current of -22 kA exceeded the tower's shielding capacity, causing a Back Flash Over phenomenon that led to system disruption. This finding was confirmed by comparing the measured voltage with the breakdown voltage of the insulator. The implications of this study highlight the importance of enhancing lightning protection systems, such as reducing tower grounding resistance and installing inductance reducers, to prevent similar disturbances in the future. This research provides valuable insights for improving the reliability and safety of power transmission networks in lightning-prone areas.

Simulation analysis of microstructure development of tricalcium silicate using the needle model of calcium silicate hydrate

This study proposes a two-scale model for tricalcium silicate (C3S) hydration to examine the microstructure of hydrated C3S paste. The needle-like morphology of a calcium silicate hydrate (C-S-H) layer, as observed in many studies, was constructed using this model based on the assumption of C-S-H needles. The boundary nucleation and growth pattern of the C-S-H needles were illustrated, and the impingement among C-S-H needles and particles was considered. The pore size distribution was calculated using the rolling sphere method for the hydrated particle system and C-S-H layer. The simulation results were compared with existing experimental data, revealing consistency for the C3S paste with different hydration times. The shape and growth parameters of the C-S-H needles were studied to model their microstructure. The microstructure constructed using this model was found to be more reasonable and could provide a more accurate description of the C-S-H morphology.

Comparative Analysis of External Lightning Protection Systems Using Protective Angle and Rolling Sphere Method in Areas That Have High Lightning Intensity

Indonesia is a tropical country with a geographical condition where 71% of its area is water. This is what coueses Indonesia is considered a country with a high density of lightning strikes. This results in buildings in Indonesia being at a high risk of damage caused by lightning strikes. According to data from BMKG, the city of Malang has a high lightning intensity, with 108 thunderstorm days per year, posing a serious threat to the Electrical Engineering Building of the Faculty of Engineering at the University of Malang. Considering the building's age and expansion on the building's side, it is necessary to evaluate the lightning protection system to determine whether the existing system is still working effectively and efficiently. Improving the system's performance against lightning disturbances can be done by analyzing the previous external lightning protection system and then evaluating it using the angle of protection and rolling sphere methods. The analysis and evaluation of the external protection system are based on PUIPP, PUIL, SNI, and IEEE standards.

PERENCANAAN SISTEM PENYALUR PETIR PADA GEDUNG - A UNIVERSITAS MPU TANTULAR CIPINANG

Mpu Tantular University is one of the leading Universities in Indonesia and has three buildings to support learing/teaching activities. Bulding-A Mpu Tantular University has 8 floors. As a vital place and has a potential for lightning strikes, because it is classified as a building with a risk of lightning strikes, Building-A need to be calculated and planned for an external lightning conductor, so that the electronic equipment inside is safe if there is a lightning strike. In determining whether or not a lightning protectionsystem is necessary, a comparative study should be carried out using the reference to the Indonesian National Standart SNI 03-7015-2004 concerning Lightning Protetion System in Buildings. The design of this lightning protection system uses the Rolling Sphere method on the Air Termination System and Multiple Rod on Earthing Termination System, so that the condition of Building-A is safe and in accordance with applicable regulation in building planing

DEVELOPMENT OF THE CALCULATION PROCEDURE ALGORITHM FOR THE CALCULATION OF LIGHTNING RODS PROTECTION ZONES ACCORDING TO THE INTERNATIONAL STANDARD IEC 62305

A series of publications on the problem of lightning protection in power stations and substations, especially in the conditions of decreasing stability of the functioning of the energy system of Ukraine is continued. In addition, the relevance of the work is substantiated by the increase in thunderstorm activity on the planet as a whole and by the data of the national energy company in Ukraine, which leads to emergency shutdowns on power transmission lines. The system of algorithms for the computational procedure for calculating the protection zones of the system, which consists of numerous rod and cable lightning conductors and protective nets, using the rolling sphere method is developed. It is noted, that the majority of strategic energy facilities in Ukraine have lightning protection systems built according to outdated standards, therefore, their inspection and modernization is necessary taking into account current regulatory documents. A generalized algorithm for constructing a protection zone using the Delaunay algorithm and previously obtained mathematical expressions has been developed, which in turn consists of sub-algorithms: constructing a polygonal grid based on the points of the coordinates of the lightning conductors, finding the areas of contact with the sphere of the vertices of the polygonal grid, constructing a grid of nodes of the analysis points, finding the height coordinates for of each analysis point, construction of the protection surface based on the grid coordinates of the analysis point nodes. The software implementation was carried out and an example of the application of algorithms was shown when calculating the protection of an operating substation with a voltage class of 150 kV. The general features of software implementation in the LiGro software complex are given. The developed software product found its application in the modernization of existing lightning protection systems of operating power facilities of Ukraine with a voltage class of 35-750 kV.

Lightning Shielding with Shading Avoidance for a Photovoltaic (PV) Farm

The special requirement of a PV farm lightning shielding system is that it should not introduce shadow on the active PV surfaces so as to avoid impaired PV generation output. By using a simple, repeatable-unit PV row made up of single or multiple PV strings, the problem of finding a cost-effective and efficient PV row lightning finial arrangement can be resolved. The shading analysis combined with the MS IEC 62305 implementation of the Rolling Sphere Method (RSM) is able to give a simple procedure that lends itself to spreadsheet calculations pertaining to PV farm lightning shielding design.

A Comparative Analysis of External Lightning Strike Protection Area Determined by Using Protection Angle and Rolling Sphere Methods

The lightning phenomenon is a natural disaster that endangers human life. The nature of grabbing objects closest to the cloud can cause fires, damage to electrical equipment, and even fatalities. The Padang Institute of Technology is a campus that has tall buildings, such as buildings B, C, D, E, and F, without an adequate lightning protection system. This is certainly a concern regarding security and safety for building users on the ITP campus. This research was conducted to reduce the risk of being hit by a lightning strike on the ITP campus. The protection system design process refers to the IEC 62305-3 standard comparing the protection angle and rolling sphere methods. Meanwhile, the procedure for calculating building requirements for a protection system or building protection level refers to the PUIPP and IEC 1024-1-1 standards. After analyzing the lightning rods in 5 ITP campus buildings by comparing the protection angle and rolling sphere methods, it can be concluded that there are still parts of the building that are not protected by the size of the installed air terminal. To overcome this, adding or adjusting the air terminal level is necessary so that all buildings are in the protection area. In addition, in conducting the analysis, the method considered the best to provide clear information on the part of the building that needs protection and the amount of the building that has been protected is the Rolling sphere method.

Penggunaan Metode Rolling Sphere untuk Pengamanan Jaringan 150 kV dari Sambaran Petir Langsung

Lightning strikes can cause protection failure at substations such as equipment damage at substations due to insulation failure or what is known as flashover. Because of that, a lightning strike protection system is needed to minimize the occurrence of direct lightning strikes to equipment and buses at the substation. This study discusses the modeling of the protection of the substation from direct lightning strikes using the rolling sphere method at the Wonosari-pedan 150 kV substation using lightning rod poles. The calculation results show that with the configuration of a lightning rod as high as 21 m and the use of a ground wire of 17.8 m it meets the safe criteria for the height of the protected area in the case study of this research.

Method of the Protected Volume LPZ0B of Lightning Air-Termination Systems

The protection system for the structures against lightning is basically constituted by means of an air termination system, down-conductors and a ground-termination system. The IEC standard 62305 introduces the rolling sphere method to analyze and to design the protected volumes of air-termination systems with a complex configuration. In order to avoid the exposure of equipment and elements on the building roof to direct lightning in the design and the following operation with new exigencies, the identification of the protected volumes LPZ0B allows taking corrective measures if needed. The suggested method assumes as reference element a pair of rods for the air termination system and proposes to identify the protected volume combining the two IEC methods of the graphical rolling sphere with the protective angle. The protected volume method proposes, as simpler first step, the mathematical calculation of the minimum protection height of prospected profile described by the rolling sphere, useful for a preliminary evaluation. As second step, the method completes the definition of the protected volume section, describing a cautionary model that replaces the circular sector of the rolling sphere with a “vase section” shape, applying the protective angle method.

Analysis of Lightning Strike Effects on Crude Oil Storage Tank Protection System at PT. Pertamina Balongan Indramayu

Main Gathering Station (MGS) Balongan Pertamina EP Asset 3 OGT is an industry engaged in the oil and gas sector by always paying attention to QHSE (Quality, Health, Safety and Environment) aspects. This industry is a national vital object categorized as a zone 1 and zone 2 hazardous area. There is a source of danger that has the potential to cause damage to equipment and people. The electrical installation used is a lightning protection system with reference to the NFPA 780-2017 standard concerning the Standard for the Installation of Lightning Protection Systems. The rolling sphere method is used to calculate the need for a lightning protection system. To calculate the need for a grounding electrode, a rod electrode grounding system is used. Construction MGS Balongan (Hazardous Construction) has a value of direct lightning strike frequency (Nd) of 0.03 lightning strikes per year with an equivalent area of building lightning strikes (Ae) of 1082.95 m2. The value (Ng) of the intensity of lightning strikes to the ground is 27.6 lightning strikes per km2 per year, the protection level is level II with a radius of 30 meters and the earth resistance value is 0.344 Ω. The design value of this calculation is in accordance with PUIL 2011 standards, namely it must be below 5Ω for the overall value of earth resistance.

Lightning rod system: mathematical analysis using the rolling sphere method

In electrical protection, there is a method of electrical protection of buildings against atmospheric discharges called the electro-geometric method or the rolling sphere method. So far, it is possible to achieve the implementation of this method graphically, that is, representing through plans and technical drawings, the protection conditions of the analyzed structure and obtaining from these graphic representations the protection parameters with the consequent errors caused by the scales and dimensions of the work plane. In the present work, a mathematical model is obtained that allows, using specific calculations, to analyze the dynamic behavior of a protection system against atmospheric discharges without worrying about the limitations given by the scales and planes. The set of equations obtained in the model allows us to determine the different parameters that define the protection system against atmospheric discharges (lightning) without depending on the graphical representation of the system's topology.

Relation between the material of roof and the risk of lightning caused damage: The rolling sphere method in the use

In the risk calculation connected to lightning protection, it is important to determine the expected average annual number of accidents caused by a lightning strike. There are different methods for that (the most popular ones are the Probability Modulated Attraction Space (PMAS) theory and the Dynamic Electro-Geometric Model (DEGM)). The paper aims to represent the correct use of the mesh method (regarding different articles and methods) in lightning protection compared to the results of the rolling sphere method.For an air-termination system, it is necessary to know not only the number of the possible lightning overall but to estimate the shielding failures as well. If there is much simplification, or some parameters or environmental factors will be inadequately neglected, that could cause incorrect risk determination.

A new-intelligent method for evaluating the lightning protection system performance of complex and asymmetric structures

- In order to model and visualize the performance of lightning and its protection system, several analytical methods such as the rolling sphere method (RSM) have been developed in which protected and unprotected areas are separated. However, in none of these methods, the scale and severity of the damage can be quantified numerically. In this paper, by using the leader progression model (LPM) in 3D space along with an intelligent algorithm named Teaching-Learning-Based optimization (TLBO), a new method is proposed to identify the vulnerable areas with the highest probability of lightning strikes. In using the TLBO algorithm, a new method for determining the critical range of current is defined and the most vulnerable points on the structure are determined, so that, based on the simulation results, the best positions of the lightning rods can be specified respectively. A sample asymmetric structure of height less than 60 meters is analyzed as a case study, and the optimal locations and heights of lightning rods are determined using the rolling sphere method and the proposed method, respectively. The simulation results validate the effectiveness of the proposed method which makes it suitable for other complex structures.

Lightning Protection of Ancient Chola Monument in South India Based on Three-Dimensional Geometric and Electro-Geometric Techniques

Lightning is one of the most commonly occurring natural phenomena which causes irrecoverable damage toedifices which include monuments that uniquely showcase global heritage. Most monuments are usually built tall since these signify symbols of victory, whereby invariably becoming vulnerable to lightning. Though several researchers have implemented various Lightning Protection Systems (LPS) to a considerable level of success, substantial statistical variations in prospective stroke currents during lightning due to factors such as climate change,complexities in geographical topography etc., present considerable challenges in obtaining a common framework for protection of structures. Hence, this research focuses on carrying out analysis based on exhaustive case-studies for an ancient United Nations Educational, Scientific and Cultural Organization (UNESCO) monument in South India. The first objective of this research is in carrying out detailed comparison of shielding effectiveness based on 3D geometric and electro-geometric LPS strategies such as Protection Angle Method (PAM) and Rolling Sphere Method (RSM). The second aims at assessment of risk in accordance with IEC 62305 for estimation of level of risk and the role of varying lightning protection levels utilizing striking distance models to obtain the appropriate choice of the location of air terminal. The third focuses on conducting cross-validation studies to assess the adequacy of the proposed location of LPS using SESShield-3D by depicting the critical zones that necessitate additional protection. In addition, shielding failure analysis of the proposed LPS is also carried out. Inferences on unshielded zones for the three-dimensional (3D) layout models of the monuments have been summarized with appropriate recommendations.

A further look at dynamic electro-geometrical model: Its fundamentals and implementation

Abstract The rolling sphere method for air termination placement on a structure is easy to apply, but it cannot be used to determine the probability of lightning strike to different points on the structure. The dynamic electro-geometrical model (DEGM) using numerical methods can be implemented to evaluate the interception efficiency of various air termination systems. The DEGM is implemented using the probability function of lightning current distribution which has a discontinuity at 20 kA. This study proposes a way to remove the discontinuity by the introduction of a continuous step function. The effectiveness of various centrally positioned air terminations on structures was also examined. Mesh air terminations are typically installed directly on the roof of protected structures. Using DEGM concept, result shows that lifting the mesh network by the penetration depth does not significantly improve the interception efficiency of the air termination network for a gable roof structure.

CONSTRUCTION PROBLEMS OF VOLUME PROTECTED BY AIR-TERMINATION ROD FOR THE UKRAINIAN NUCLEAR POWER PLANT UNDER STANDARD EN 62305

Mathematical analysis of the rolling sphere method was performed to develop a model for constructing of volume protected by rod air-termination in accordance with EN 62305:2012 for the protection of nuclear power plants objects from direct lightning strike. The necessity of development of the corresponding mathematical model for similar objects is shown, and the direction of its realization with the help of decomposition method is proposed. The mathematical models for calculation of protection zones of single and double air-termination rods of arbitrary height and location are developed. Directions of further researches are formed.

Lightning Shielding Analysis on Ships

Calculations of the expected number of lightning strikes on three ship models are presented with comparative application of various lightning attachment models and stroke current distributions. Depending on the ship structure, on coastal areas, a lightning strike on a ship is expected approximately every two years. Application of the rolling sphere method highlighted as regions exposed to lightning strikes not only high masts but also lower structures in the cases of ships with less dense geometry. A new method for the lightning protection of critical masts that combines a shielding analysis procedure and a statistical lightning interception model was also proposed and applied to specific masts of the ship models in order to evaluate whether shielding from nearby higher masts is achieved and to define the proper height and installation position of a new rod. Proximity effects, interception probability, and choice of the ground reference level arise as parameters that affect the results of the shielding analysis, especially when the equipment under protection is the highest structure on the ship.

Estimation of the electric fields and dielectric breakdown in non-conductive wind turbine blades subjected to a lightning stepped leader

In this paper, the electric fields in the wind turbine blades due to the lightning stepped leader are studied, and the dielectric breakdown is assessed. The developed finite element analysis (FEA) includes the full length of the leader and enables one to incorporate various uniform and non-uniform charge density models. The lightning striking distance is calculated using the rolling sphere method. The electric field in a horizontal axis wind turbine with three blades representing Sandia 100 m All-glass Baseline Wind Turbine Blades (SNL 100-00) at three different lightning protection levels (LPL) is computed and compared to the dielectric breakdown strength of the blades. The dielectric breakdown strength of the blades is evaluated based on the experimental data. The results show that the tip region of the blade is the most vulnerable to the dielectric breakdown with the safety factor as low as 1.32 at LPL I. Copyright © 2016 John Wiley & Sons, Ltd.