Optimization of Underground Power Cable Systems

2021 ◽  
pp. 141-170
Author(s):  
Paweł Ocłoń
Keyword(s):  
Power Cable ◽  
Cable Systems ◽  
Underground Power Cable

scholarly journals Analysis of an application possibility of geopolymer materials as thermal backfill for underground power cable system

2020 ◽  
Author(s):  
Paweł Ocłoń ◽  
Piotr Cisek ◽  
Marcelina Matysiak
Keyword(s):  
Thermal Conductivity ◽  
Economic Benefits ◽  
Environmental Benefits ◽  
Power Cable ◽  
Closed Cycle ◽  
Cable System ◽  
Material Costs ◽  
Cable Systems ◽  
Underground Power Cable ◽  
By Products

Abstract The circular economy is a closed cycle that allows one to reuse the industrial waste, as well as minimize the energy and resources losses during the production process. This paper presents an innovative idea of the application of a geopolymer cable backfill for underground power cable system installation. The closed cycle, in this case, is formulated as follows: the primary resource is the waste from the combustion of fossil fuels, i.e., fly ash that is utilized to form the geopolymer matrix. The geopolymer then is used as thermal backfill in underground power cable systems. Utilization of combustion by-products in the form of a geopolymer is a highly profitable solution since landfill waste disposal, in this case, generates considerable costs for the electrical energy producers. In typical applications, geopolymers are used as insulators. By adding individual components, the thermal conductivity of 2.0 W/(m K), higher than of typical thermal backfills (Fluidized Thermal Backfill), which value is close to 1.5 W/(m K), is reached. What is very important, geopolymers can absorb water better than typical sand–cement mixtures. As a result, a high thermal conductivity with the temperature increase is maintained. The application of geopolymers as thermal backfills has the potential to improve the flexibility of underground power cable systems, as well as to minimize the material costs of installation. The case study is presented to show the economic benefits of using the combustion by-products as a geopolymer thermal backfill. The finite element method model of an underground power cable system is developed, and optimization of backfill dimensions is provided to minimize the material costs using the geopolymer thermal backfill and to maximize the underground power cable system performance. The main result of this paper is that the application of geopolymers leads to a decrease in underground power cable system costs, compared to traditional backfill (sand–cement mixture). The reason is the higher value of thermal conductivity, which allows selecting a cable with a smaller cross-sectional area. Also, the environmental benefits of geopolymer application for cable bedding are discussed. Graphic abstract

Characteristics and Reduction of Sheath Circulating Currents in Underground Power Cable Systems

2004 ◽  
Vol 1 (1) ◽  
Author(s):  
C.K. Jung ◽  
J.B. Lee ◽  
J.W. Kang ◽  
Xinheng Wang ◽  
Yong-Hua Song
Keyword(s):  
Transmission System ◽  
Power Cable ◽  
Special Equipment ◽  
Transmission Systems ◽  
Circulating Current ◽  
Cable Systems ◽  
Underground Power Cable ◽  
Formation System ◽  
Circulating Currents

Sheath current can cause sheath loss and reduce the permissible current of a power cable transmission system. High sheath current is usually caused by mixed cable burying formation, different length between sections, poor connection of the bonding leads, and connection of distribution cable onto transmission systems. This paper analyses the characteristics of sheath circulating current at various conditions and presents a useful method to reduce it in a mixed burying formation system. It can effectively reduce the current by up to 90%. The method is validated by practical measurements and simulations using ATP, and has been implemented in actual systems. In addition, a special equipment is designed to measure and analyze the sheath circulating current. It can measure and analyze nine currents at a same time.

scholarly journals Evolution of Temperature Field around Underground Power Cable for Static and Cyclic Heating

Energies ◽  
2021 ◽  
Vol 14 (23) ◽  
pp. 8191
Author(s):  
Shahbaz Ahmad ◽  
Zarghaam Haider Rizvi ◽  
Joan Chetam Christine Arp ◽  
Frank Wuttke ◽  
Vineet Tirth ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Thermal Conductivity ◽  
Mass Transfer ◽  
Heat And Mass Transfer ◽  
Weather Conditions ◽  
Nonlinear Dependence ◽  
Transfer Model ◽  
Power Cable ◽  
Cable Systems ◽  
Underground Power Cable

Power transmission covering long-distances has shifted from overhead high voltage cables to underground power cable systems due to numerous failures under severe weather conditions and electromagnetic pollution. The underground power cable systems are limited by the melting point of the insulator around the conductor, which depends on the surrounding soils’ heat transfer capacity or the thermal conductivity. In the past, numerical and theoretical studies have been conducted based on the mechanistic heat and mass transfer model. However, limited experimental evidence has been provided. Therefore, in this study, we performed a series of experiments for static and cyclic thermal loads with a cylindrical heater embedded in the sand. The results suggest thermal charging of the surrounding dry sand and natural convection within the wet sand. A comparison of heat transfer for dry, unsaturated and fully saturated sand is presented with graphs and colour maps which provide valuable information and insight of heat and mass transfer around an underground power cable. Furthermore, the measurements of thermal conductivity against density, moisture and temperature are presented showing positive nonlinear dependence.

scholarly journals Multiobjective optimization of underground power cable systems

Energy ◽  
2021 ◽  
Vol 215 ◽  
pp. 119089
Author(s):  
Paweł Ocłoń ◽  
Monika Rerak ◽  
Ravipudi Venkata Rao ◽  
Piotr Cisek ◽  
Andrea Vallati ◽  
...  
Keyword(s):  
Multiobjective Optimization ◽  
Power Cable ◽  
Cable Systems ◽  
Underground Power Cable

A Discussion on recent advances in heavy electrical plant - Underground power cables

1973 ◽  
Vol 275 (1248) ◽  
pp. 193-203 ◽  
Keyword(s):  
Power Transmission ◽  
Power Cable ◽  
Power Cables ◽  
Cable System ◽  
Insulating Materials ◽  
Cable Systems ◽  
Underground Power Cable ◽  
Underground Power Cables ◽  
Near Future ◽  
Further Development

Up to the present, effectively all underground power transmission needs have been satisfied by the use of conductors insulated with impregnated paper. In particular, in recent years, the oil-filled cable system using cellulose paper impregnated with oil under pressure has been further developed to meet all immediate and near future needs for higher voltage and higher current power transmission underground. With modem materials and technology, are there more economical solutions and can the needs of the longer future term be met? The basic electrical, thermal, mechanical and reliability constraints which are exerted upon the design of supertension underground power cable systems are considered. The limitations upon further development of the oil-filled cable system are identified. Also, indications are given of the potentials of new insulating materials and novel constructions of cable to provide more economical solutions and greater power transmission capabilities.

Sign in / Sign up

Export Citation Format

Share Document