A Study on Lightning Protection Measures for Railway Signalling Systems

2012 ◽  
Vol 132 (11) ◽  
pp. 881-884 ◽  
Author(s):  
Hideki Arai
2020 ◽  
Vol 11 (7-2020) ◽  
pp. 66-72
Author(s):  
Liubov A. Belova ◽  

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.


Fire Safety ◽  
2021 ◽  
Vol 38 ◽  
pp. 24-31
Author(s):  
Yu. Rudyk ◽  
O. Nazarovets ◽  
I. Golovatchuk ◽  
N. Beznos

Introduction. Today requires the introduction and arrangement of modern enterprises automation of the technological process using various electronic and electrical equipment. The breakdown of one sensor leads to a stoppage of the technical process and thousands of losses. This equipment is sensitive to impulse overvoltages that occur for various reasons, as well as when hit by lightning. There is a misconception that the danger of lightning arises only when struck directly, forgetting about the socalled secondary phenomena, namely electromagnetic and electrostatic pulses. Pulse overvoltage is a short-term increase in voltage above the allowable value. Lightning protection systems are designed and designed to protect objects from dangerous lightning.Purpose. Given the automation of the process and the saturation of boilers with electronic and electrical equipment, there is a high risk of lightning and high potentials, which can lead to large-scale accidents. The purpose of this article is to validate the risk indicators for the boiler environment that occur during a thunderstorm.Methods. The use of various methods of calculation, assessment and ordering of risks during the design and layout of the system allows to implementation system lightning protection of buildings, equipment and people. General principles of risk assessment for the boiler environment must take into account: risk and determine the need for protection; the contribution of various risk components to the overall risk; the effect of various protection measures to reduce risk; selection of protection measures taking into account their economic efficiency.Results. Neglecting the high risk of a dangerous event leads to excessive damage and m irreparable losses, with which a person or community will not be able to achieve sustainable development. Therefore, it is a comprehensive, systematic approach to achieving safety, starting from the assessment stage, should take into account both the characteristics of the hazard, including a fire in the relevant facilities, and personal, the individual risk of death or injury. Lightning is an unpredictable natural event, no one in the world fully understands the mechanism of lightning and it is impossible to provide 100% protection under any circumstances under any standardization. For this purpose, the following calculations are given: loss of human life, including injuries; loss of the ability to provide public services; losses of cultural heritage and economic value of the building (structure) and economic losses required for the installation and operation of the system. Based on the obtained data, it is seen how the reduction of each risk is achieved depending on the proposed solution and the economic effect in general.Conclusion. Statistics on deaths and injuries from lightning hazards, losses from damage to property, buildings and struc-tures confirm that in risk assessment, which is standardized in DSTU EN 62305-2, it is necessary to introduce a methodology that would meet the conditions of Ukraine. The arrangement of the lightning protection system depends on the risk assessment, the reaction of the owner, the influence of control bodies. Therefore, it is important to decide on fire protection measures in lightning risk assessment procedures, but it can also be taken regardless of the results of the risk assessment where there is a desire to avoid unacceptable risk. Equipment that is often associated with two different services, e.g. power lines and data lines suffer a lot of surge damage. This case is not covered by the RX risk component. However, appropriate protection measures can be selected and established (see IEC 62305-4).


Author(s):  
Paulius Stankaitis ◽  
Alexei Iliasov ◽  
Tsutomu Kobayashi ◽  
Yamine Aït-Ameur ◽  
Fuyuki Ishikawa ◽  
...  

AbstractThe decentralised railway signalling systems have a potential to increase capacity, availability and reduce maintenance costs of railway networks. However, given the safety-critical nature of railway signalling and the complexity of novel distributed signalling solutions, their safety should be guaranteed by using thorough system validation methods. To achieve such a high-level of safety assurance of these complex signalling systems, scenario-based testing methods are far from being sufficient despite that they are still widely used in the industry. Formal verification is an alternative approach which provides a rigorous approach to verifying complex systems and has been successfully used in the railway domain. Despite the successes, little work has been done in applying formal methods for distributed railway systems. In our research we are working towards a multifaceted formal development methodology of complex railway signalling systems. The methodology is based on the Event-B modelling language which provides an expressive modelling language, a stepwise development and a proof-based model verification. In this paper, we present the application of the methodology for the development and verification of a distributed protocol for reservation of railway sections. The main challenge of this work is developing a distributed protocol which ensures safety and liveness of the distributed railway system when message delays are allowed in the model.


2005 ◽  
Vol 46 (2) ◽  
pp. 118-123
Author(s):  
Hideki ARAI ◽  
Hiroyuki SUGAHARA ◽  
Kazutoshi SATO

2013 ◽  
Vol 2 (2) ◽  
pp. 97-112
Author(s):  
A. Morant ◽  
R. Karim ◽  
P.-O. Larsson-Kråik

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