Construction Technology of Lightning Protection Devices in Building Electrical Installation Engineering

To better improve the electrical safety of buildings and fulfill the role of lightning protection and grounding,this article combines cases and discusses seven aspects of lightning protection devices’construction technology.These aspects include the lightning protection classification of buildings,air terminals,down conductors,grounding devices,division of lightning protection zones,and lightning electromagnetic pulse shielding.Through the introduction of this article,readers can gain a comprehensive understanding of the application and value of lightning protection grounding construction technology in building electrical installation projects.

Single-phase-to-ground fault protection based on zero-sequence current ratio coefficient for low-resistance grounding distribution network

Definite-time zero-sequence over-current protection is presently used in systems whose neutral point is grounded by a low resistance(low-resistance grounding systems).These systems frequently malfunction owing to their high settings of the action value when a high-impedance grounding fault occurs.In this study,the relationship between the zero-sequence currents of each feeder and the neutral branch was analyzed.Then,a grounding protection method was proposed on the basis of the zero-sequence current ratio coefficient.It is defined as the ratio of the zero-sequence current of the feeder to that of the neutral branch.Nonetheless,both zero-sequence voltage and zero-sequence current are affected by the transition resistance,The influence of transition resistance can be eliminated by calculating this coefficient.Therefore,a method based on the zero-sequence current ratio coefficient was proposed considering the significant difference between the faulty feeder and healthy feeder.Furthermore,unbalanced current can be prevented by setting the starting current.PSCAD simulation results reveal that the proposed method shows high reliability and sensitivity when a high-resistance grounding fault occurs.

Lightning Protection for the Computer Room of Electronic Information Systems

An electronic information system is composed of multiple groups of components. With the improvement of technology, its accuracy is getting higher and higher. The voltage during normal operation is only a few volts, and the information current is only microamp, so the withstand voltage to lightning electromagnetic pulse is extremely low. In this paper, the negative impact of lightning and static electricity on the computer room of an electronic information system was analyzed firstly, and then the design for the lightning protection of the computer room was discussed.

Research on Common Grounding Electrode Technique in HVDC

This paper discusses the characteristics of DC transmission common system ground electrode type and shared ground electrode, established the mathematical model of two circuit DC systems share ground electrode, analyze effects of the shared loop ground DC transmission system electrode on the operation of HVDC system size under different operation modes, and compare with the independent ground electrode, ground electrode impact on environment under different operation mode, and the paper finally puts forward some solving measures for the influence of the shared ground electrode on the environment and public ground electrode effects on DC system operation problems.

Natural Ionizing System of Electrical Protection and Energies against Atmospheric Discharges （Lightning）

This is the new highest technology, 100% Venezuelan and unique in the world, technological innovation, world patent for maximum protection, security and zero risk （0） to all electrical and power generation systems： hydroelectric and thermoelectric power plants, wind, nuclear and solar power plants, etc.; it is the only technology around the world that has the potential to disperse and propagate to land mass the enormous energies associated to the atmospheric discharges （lightning）, which are in the order： 200,000 to 500,000 Amperes; 1,000 million kilowatts and high-level transient voltage of 100 million volts. This new high technology is the solution to the paradigm of Benjamin Franklin and it is the mechanism to end ＂blackouts＂ that produces so many damages and losses of billions of dollars to both generators and users of electrical service, throughout the world.