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The dispersion characteristics of the grounding electrode is an important characteristics of tower grounding network. The electromagnetic parameters of the material have a great influence on the dispersion characteristics of the material with power frequency and impulse sources. In this paper, several kinds of metal and non-metallic grounding materials are selected that are often used for power system...
This work deals with the design of a Lightning Protection System to the rocket launcher located in the Barreira do Inferno Launch Center. For its development the technical standards ABNT NBR 5419/2015 and IEC 62305 were used as main references. The Electrogeometrical Method (Rolling Spheres) was used for the development of the project, chosen after a thorough analysis of the other methods and the...
Measurements have been conducted to show that glowing connections can occur in DC circuits at voltages as low as 12Vdc. Properties of glowing connections for dc circuit conditions for a variety of electrically conductive materials is presented. Results reveal glowing connection characteristics for commonly used conductor material found in electrical circuits (copper and steel) for 12V, 24V, and 48V...
The ICP (inner corona protection) of the stator coil is to reduce the concentrated electric field at the corner and to release the electrical stress in the filler. With these functions the life of the coil can be extended and the tip-up values can be lowered. But the properties of itself such as resistivity and length (the distance between two high voltage touch points) also have influence on performances...
Different from permanent magnet synchronous machine, switched reluctance motor(SRM) is featured as high local flux density, high current variation ratio in the winding with medium, high power and high speed. Therefore, hot spots in the winding could be caused by eddy current effect. When current flows through winding, skin effect is generated by the high frequency alternating current due to the high...
Grounding system plays very important role in AC substation station for person and equipment safety. Proper design of grounding system is achievable by following IEEE Std-80 on safety in AC substation grounding but novice professionals find it not easy to use. The advantage of this paper presents evaluation of grounding system for AC substation by case studies presentation thus easing the understanding...
Aluminium is widely used as conductor material for power cables, but corrosion taking place under specific circumstances can have impact on its reliability. Aluminium corrosion under the influence of an alternating current was studied experimentally. Submerged cable segments with inflicted damage exposing the conductors resulted in a continuous corrosion of the conductor material. Effects of temperature...
The traction current is returning to the supply source crossing the return circuit to the 25 kV single-phase AC power source. The return circuit consists of the running rails, which are connected by conductors to the joint coils terminals, and the return feeder to the traction substation. The connecting conductors (connection ropes) are subjected to thermal stresses due to the intense currents which...
The paper presents an impact analysis of the thermal stresses of electrical equipment impact on the environment temperature. To accomplish this were determined the steady-state overtemperatures and thermal time constants for three different sections of a busbar system, from a low voltage electric switchboard, in order to determine the thermal stresses for each case. To see how much the value of thermal...
Wound components typically represent approximately 50 % of the total mass of a power converter, consequently minimising the mass and volume of transformers and filter inductors is an important challenge in the design of compact power dense converters in transport and other demanding applications. The research described in this paper contributes to a body of work investigating design tools and new...
This work presents the thermal reliability test results of a metaconductor device on a glass substrate. Custom thermal cycling testing between room temperature and 100 °C has been performed for both Cu/Ni and Cu/NiFe metaconductor based transmission lines. The overall electrical performance has been well preserved between 300 kHz and 12 GHz. After a high temperature annealing treatment with 400 °C...
This work presents a coaxial transmission line constructed with additive manufacturing (3D printing) technologies. The coaxial structure is primarily air dielectric and, thus, is relatively low loss and is capable of high frequency transmission, demonstrating good transmission above 10~GHz. Additionally, a first order band-pass filter is demonstrated along with a comparison to an equivalent planar...
Co/Cu composite interconnect systems were studied. Since wide Cu lines require a diffusion barrier which is simultaneously applied also to fine Co lines to reduce Co volume fraction, through-Cobalt Self-Formed-Barrier (tCoSFB) was employed to thin down TaN barrier to <1 nm which works as an adhesion layer for Co lines. Line R of fine Co lines was reduced by 30% successfully. The Co/tCoSFB-Cu composite...
A newly developed copper foil which is chemically processed has been introduced as nano anchoring copper foil for Printed Wiring Board (PWB). This treatment technology enables good adhesion even on the nano-scale surface roughness by conditioning a copper surface of nano-scale anchoring structure. The surface roughness of the copper foil affects fine patterning capability and transmission loss. Fine...
Current mobile broadband network system may limit the growth of mobile services. In order to accommodate larger network capacity and higher speeds, the 5th generation (5G) mobile communication system is desired instead of 4G network technologies, known as 5G. It is expected to start its initial service in 2020[1]. 3.5 billion Connected things will be use in 2020 in automotive sector due to the Internet...
This work addresses the design and the fabrication of small scale square planar coils with high density of turns and self inductances up to 170 μH. First, the modified Wheelers formula is used to determine the optimal number of turns in order to achieve the highest inductance. Then, an effective process flow based on polyimide (PI) and copper processing is presented, and the key aspects of the processing...
Direct buried is the most common and widely used installation method for underground power cable system. However, the installation characteristics that have been used in recent times do not have an optimum level of cable ampacity which could not support the increasing demand of electrical energy utilization. Besides, the existing installation characteristics have deteriorated the operational lifetime...
Laser cladding allows for a fast, flexible and direct plotting of electric conductive structures on polymer based substrates. The surface of the substrate is selectively melted by a focused laser beam. Simultaneously, a metal powder is lead through a powder nozzle. This nozzle is oriented laterally or coaxially to the laser beam. As a result, a molten bath of substrate and powder material is created...
Axial Field Permanent Magnet Motor (AFPM) can be easily integrated into wheel-hub motor of Electrical Vehicle (EV) as impact structure and light weight. Improved hexagonal asymmetry coil is presented in Printed Circuit Board (PCB) stator of coreless AFPM. Geometry parameters of coil shape is optimized. According to the structure characteristics of coreless AFPM, dimension formulas of PCB coil are...
Electrodynamic (ED) forces influencing upon lightning protection (LP) components in some typical LP system configurations and conditions are studied. These include: various angles between conductors, their finite lengths, round and flat bar cross-section, grid of conductors, various heights of conductor holders, placement of conductors above metallic cladding and reinforced concrete, various materials,...
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