摘要 :
Gas insulated transmission line (GIL) is an advanced power transmission mode. Since the extension of this kind of equipment is relatively long, the grounding design and layout of the GIL will have a direct impact on personal safet...
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Gas insulated transmission line (GIL) is an advanced power transmission mode. Since the extension of this kind of equipment is relatively long, the grounding design and layout of the GIL will have a direct impact on personal safety and the stability operation of equipment, which should be given full attention. In order to ensure the safe and stable operation of GIL, it needs reasonably design and arrangement of the integrated grounding system in the GIL pipelines. This study designed corresponding grounding scheme for the integrated grounding system of underground GIL pipelines combined with a 550 kV/4000 A GIL. The corresponding simulation model of the integrated grounding system was established with specific parameters of the GIL. The calculation results show that the grounding resistance of the integrated grounding system is 0.217 Ω, which is less than the grounding requirement value of 1 Ω, and it reduces 28.9% compared with the simulation model without considering the natural grounding body. In addition, the step voltage and touch voltage are reduced by 79.91 and 48.97%, respectively. The research results can give some references for the integrated grounding system design of GIL engineering.
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摘要 :
This paper deals with the possibility of installing a double-circuit gas insulated transmission line (GIL) in the pilot tunnel of the planned new railway galleries Bolzano (Italy)- Innsbruck (Austria). This EHV transmission line c...
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This paper deals with the possibility of installing a double-circuit gas insulated transmission line (GIL) in the pilot tunnel of the planned new railway galleries Bolzano (Italy)- Innsbruck (Austria). This EHV transmission line could represent a new fundamental step in reconstructing the transnational networks. The high GIL power ratings together with very low power losses would be a strong and highly efficient transmission tie between Italy and Austria particularly useful for the future European Market. The steady-state regime of the line and the electro-magnetic field impact are analyzed. Moreover, the paper discusses the necessary studies to be carried out and the problems that have to be faced.
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摘要 :
This paper deals with the possibility of installing a double-circuit gas insulated transmission line (GIL) in the pilot tunnel of the planned new railway galleries Bolzano (Italy)- Innsbruck (Austria). This EHV transmission line c...
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This paper deals with the possibility of installing a double-circuit gas insulated transmission line (GIL) in the pilot tunnel of the planned new railway galleries Bolzano (Italy)- Innsbruck (Austria). This EHV transmission line could represent a new fundamental step in reconstructing the transnational networks. The high GIL power ratings together with very low power losses would be a strong and highly efficient transmission tie between Italy and Austria particularly useful for the future European Market. The steady-state regime of the line and the electro-magnetic field impact are analyzed. Moreover, the paper discusses the necessary studies to be carried out and the problems that have to be faced.
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摘要 :
The UHV gas-insulated transmission line (GIL) has the advantages of large transmission capacity, high operation reliability, and environmental friendliness. It is suitable for the power transmission of hydropower stations and nucl...
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The UHV gas-insulated transmission line (GIL) has the advantages of large transmission capacity, high operation reliability, and environmental friendliness. It is suitable for the power transmission of hydropower stations and nuclear power stations and the restricted environmental or geographical conditions. China is constructing a single-phase length of 5.8 km from Suzhou to Nantong UHVAC GIL over the Yangtze River project. However, due to the large size of the UHV GIL, the long standard units, and the large capacity, it is of great significance to study the motion of metallic particles near the disc insulator for the safety and stability of UHV GIL. Taking the typical insulation structure of UHVAC GIL as an example, a numerical model of the movement of spherical metal particles near the conical insulator was established. The influence of different initial positions, different loading voltages, and different particle quality on the motion characteristics of the particles was analysed. The conclusions of the study provide theoretical support for the design of insulation structure and engineering application of UHVAC GIL.
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摘要 :
It is very important to know the insulation recovery time after arc interruption for selecting the adequate reclosing dead time of rapid auto-reclosing on transmission lines. In order to study insulation recovery characteristics a...
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It is very important to know the insulation recovery time after arc interruption for selecting the adequate reclosing dead time of rapid auto-reclosing on transmission lines. In order to study insulation recovery characteristics after arc interruption on UHV (1000 kV class) transmission lines, many tests were carried out. Full size insulator assemblies were used for measurements of insulation recovery characteristics after arc interruption, and the behavior of post arc gases, which strongly influence the insulation recovery characteristics, was investigated. In this paper the authors describe the behavior of post arc gases after arc interruption of UHV transmission lines.
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摘要 :
In this letter the dynamics of wire particles in a coaxial gas insulated transmission line (GITL) system with coated electrodes under AC voltage are studied using a computational algorithm. The possibility of the SF/sub 6/ gas ins...
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In this letter the dynamics of wire particles in a coaxial gas insulated transmission line (GITL) system with coated electrodes under AC voltage are studied using a computational algorithm. The possibility of the SF/sub 6/ gas insulation breakdown due to the presence of metallic contaminants was computed at different applied voltages and gas pressures.
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摘要 :
A gas insulation structure called C-GIL, applicable to transmission lines or substation buses, is proposed. It consists of three conductors insulated by SF/sub 6/ or a gas mixture near atmospheric pressure in a rectangular compart...
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A gas insulation structure called C-GIL, applicable to transmission lines or substation buses, is proposed. It consists of three conductors insulated by SF/sub 6/ or a gas mixture near atmospheric pressure in a rectangular compartment (2*2 m/sup 2/ for 500 kV class). Compared with conventional cocylindrical types used at higher gas pressures, it has advantages such as reduced effect of conductive particles, high current capacity, and ease of construction and repair. The main features of C-GIL, insulation design for 500 kV based on the field calculations, and breakdown characteristics in the presence of a wire are discussed.
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摘要 :
The operating constraints involved in power transmission of long AC cable links are presented and here throughout developed. The possibility of transmitting high power rating is examined and the transmission length limits are eval...
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The operating constraints involved in power transmission of long AC cable links are presented and here throughout developed. The possibility of transmitting high power rating is examined and the transmission length limits are evaluated. The procedure, which uses the great computation and graphical facilities of modern computers, is essentially based on the classical transmission equations and their pertaining diagrams. It has been particularly applied to XLPE cables and gas-insulated lines but it is worth applying to any distributed-parameter transmission line (including overhead lines). The capability chart proposed in the paper is a useful tool to highlight the operating characteristics of a cable link and a guide to evaluate the results of different degrees of reactive compensation. The authors hope that the results can offer the transmission system operators very effective means in order to evaluate the existing and future underground cable links.
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摘要 :
The gas-insulated transmission line (GIL) has the advantages of large transmission capacity, high operation reliability and environmental friendliness. It is suitable for the high voltage direct current (HVDC) power transmission o...
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The gas-insulated transmission line (GIL) has the advantages of large transmission capacity, high operation reliability and environmental friendliness. It is suitable for the high voltage direct current (HVDC) power transmission of hydropower stations or nuclear power stations. However, due to the serious surface charge accumulation problem of the cone-type insulator under DC, its flashover performance is reduced, which restricts the engineering application of HVDC GIL. In this study, a charge transport model of SF
6
gas and epoxy is established for a 550 kV cone-type insulator and the charge accumulation characteristics of the concave and convex surfaces of the cone-type insulator are obtained. Computational results show that the gas conductivity around the cone-type insulator is not uniform due to the charged particles drifting under a constant electric field. Compared with the AC, the difference of the electric field distribution caused by charge accumulation under DC stress is analysed. Based on the established model, the influence of the gas ion-pair generation rate and epoxy volume conductivity on the charge accumulation on the surface of 550 kV cone-type insulator was studied. This study is helpful to further optimise the geometry and material properties of the cone-type insulator and reduce the surface charge accumulation and critical area electric field to improve HVDC GIL insulation design.
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摘要 :
The author introduces the notion of the risk of burn-through, borrowed from the risk of failure widely used in the statistical approach to insulation coordination, to evaluate the capability of gas-insulated equipment and substati...
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The author introduces the notion of the risk of burn-through, borrowed from the risk of failure widely used in the statistical approach to insulation coordination, to evaluate the capability of gas-insulated equipment and substations (GIS) to withstand burn-through due to internal arcs. A sensitivity analysis performed to identify the main parameters affecting the risk of burn-through showed that the risk increases with the mean fault current. Both the fault-clearing characteristics of the switching apparatus and the GIS design, namely the envelope thickness and the GIS section length between two consecutive insulators, were found to have a significant influence on the risk of burn-through. To keep the risk of burn-through reasonably low, appropriate coordination must be made among the fault-clearing characteristics of the switching apparatus, the GIS design, and the distribution of the local fault currents.
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