Cable technology

The anchor cables of slopes are affected by long-term environmental corrosion, geotechnical creep, and adverse weather, resulting in gradual loss of tensile force, which can lead to structural failure and subsequent safety accidents. The authors of this paper conducted research based on the magnetic induction density distribution characteristics of permanent magnets, including model derivation, theoretical simulation, and indoor experiments, aiming to propose a new anchor cable force monitoring technology with high sensitivity, strong applicability, and good stability. Based on the molecular circulation model and the Biot–Savart law, the analytical expression of the spatial magnetic field distribution of a rectangular permanent magnet was derived and, combined with the stress–strain relationship characteristics of anchor cables, a theoretical model for the relationship between anchor cable tensile force and magnetic induction density was established. MATLAB (R2018b) was used to simulate and analyze the spatial magnetic field distribution and the force–magnetism relationship. The analysis showed that the magnetic induction density along the central axis of the permanent magnet approximately exhibited a symmetrical quadratic curve distribution, and its value was significantly negatively correlated with the anchor cable force. Based on this, a new anchor cable force monitoring technology was proposed, and an indoor experimental platform was established. The indoor experimental studies further confirmed the negative correlation between force and magnetism (i.e., as the tensile force increases, the magnetic induction strength decreases, and as the tensile force decreases, the magnetic induction strength increases). The fitting results of the force–magnetism curve show that a quadratic function can better describe the correspondence between magnetic induction density and anchor cable force. Reproducibility analysis of the experimental data showed low dispersion in magnetic induction values under various design loads, along with good stability, validating the effectiveness and applicability of the proposed anchor cable force monitoring technology.

13 - Cable technology

In the international and regional interconnection of the power grid, submarine cable transmission engineering is a critical component for network construction and optimizing energy allocation. This paper describes the condition of the regional power grid interconnection of submarine cable projects around the world since the 1990's and the development trends of cross ocean power grid connection projects in different countries. It summarizes and analyses the electricity transmission method applied in submarine cable projects. It provides references and insights to the research for electricity transmission method used in the cross ocean interconnecting projects and to the choice of transmission method adopted in the interconnecting projects. It points out advantages and shortcomings of the direct current transmission system applied in submarine cable projects and the strong point that VSC HVDC is used in the submarine cable projects. In the process of achieving grid internationalization, regional power grid interconnection and optimal energy allocation, submarine cable transmission engineering is an important component for network construction. In recent years, with the development of international power transmission technology, together with the trend of economic integration, optimal allocation of energy and reducing the impact on the environment, the cross-sea power transmission, manufacturing technology of the submarine cable and submarine cable engineering technology continues to make progress. The construction of submarine cable is constrained by geographical construction conditions, ocean engineering conditions and construction equipment. The construction involves a wide range of technology with a large investment scale and complex techniques. This construction would be separated into two stages. The preparation stage includes engineering design, submarine cable routing, cable manufacturing and transportation. The construction stage is composed of submarine cable routing orientation, submarine cable laying, on-land equipment installation, test and commissioning and quality control of the work. The main elements of the submarine cable transmission project construction includes regional power grid interconnection across the waters, power supply to oceanic islands and an oil drilling platform and transport marine renewable energy through grid-connected. Impacted from international energy resource optimal utilization, improving national energy safety and reliability from each country and realizing power exchange among different countries, the submarine cable construction can continue to push the international energy structure change, establishing global energy structure for a further development.

CFRP lamella stay-cable and its force measurement based on microwave radar

This paper presents reasons and constraints, which have made Automated People Movers (APMs) extremely expensive for airport applications, and subsequently prevented smaller airports from considering technological solutions for their surface traffic problems. It also offers some recipes for better and more diversified use of People Mover technologies and project implementation techniques for both intra-airport and airport transit link applications. Furthermore, the paper describes the overwhelming ratio of feasibility studies versus installations often due to misleading presentations of technological opportunities as well as explains the unnecessary constraints imposed on cable technologies, which are ideal for most airport applications. It presents selected new technologies holding promise for medium and smaller airports. In addition, the paper discusses the specification impact on innovation and cost, as well as reversed trends in procurement methods. To summarize, the paper presents the status of the airport People Mover industry in the beginning of the new millennium when the airport market is booming, but continues to be dominated by a single technology that was developed in the early 1960's.

This paper presents a variety of viewpoints from engineers within the power cable industry as to how current trends in the cable industry will influence future cable designs, particularly with polymeric insulation, lapped dielectrics, and improved diagnostic techniques. The use of high-temperature superconductors and designer polymers as well as the possible availability of conducting polymeric materials is also considered.The paper first reviews how the design of distribution cables has differed historically around the world, the major differences being allied to the systems. Designs largely have been divided into two main categories: those countries following U.K. and European practices, and those having adopted the U.S. system design. However, these differences, such as the use of three-phase cables in the U.K. as opposed to single-phase cables in the U.S., are not so obvious nowadays. Installation practices are becoming rather more standardized, such as the use of ducts, directional drilling, etc. The predominant primary insulation is cross-linked polyethylene (including tree-retardant XLPE), which is used all around the world. Some constructional differences such as the “dry” and “wet” designs persist. The paper then discusses cables from the mid–twentieth century projected into the twenty-first century. Highlighted are the opportunities that will present themselves in the twenty-first century: fluid-filled cables, XLPE cables, intelligent cables, and designer polymers that optimize performance and economic advantages of buried cables. It then focuses on economic trends, power generation trends, lower-cost underground systems, overhead line/underground cables, and materials and environmental trends including use of high-temperature conductors to up-rate overhead circuits. The trend will be toward greater security and utilization using on-line diagnostics, greater circuit diversity due to distributed generation and lower cost cable systems, and extensive use of polymeric materials having low environmental impact.A futuristic view of energy cables in the year 2050 is presented. Discussed are the elements of the “info-energy cable,” the advantages of the cable technology, and the advantages for the network configuration. A realistic view of tendencies in cable systems technology over the next decade is outlined. Also discussed is choice of cable for subsea power links: choice of cable design that exists for subsea power links, the merits of the various designs, installation of submarine cables, protection of submarine cables, new challenges in HVdc submarine cable systems, and future developments. The manufacture and installation of long continuous lengths of subsea power cable is discussed with reference to some key installations. The paper goes on to examine the Kontex HVdc link between Denmark and Germany. The cable link has been in commercial operation since 1996, and with a total length of 172 km and a transmission capacity of 600 MW at 400 kV is still unique worldwide. Details of the link together with its installation and commissioning are explained.Gas-insulated transmission lines are also discussed together with whether they are ready for real-world transmission systems.

10 - Cables in buildings and between buildings

This third edition to the Handbook of Oceanographic Winch, Wire and Cable Technology has been prepared to provide a reference and guide for the operation, handling and care of winches, wires, cables and oceanographic rope for the operators and scientists of the oceanographic community. Further references on specific subjects can be found in the various chapters. Since the original writing of this handbook the operators of oceanographic ships have significantly improved the reliability and safety of deck equipment and deck operations. Some credit must be given to this handbook and the increased interest of both the funding agencies and the ship operators in striving for a higher level of operation and maintenance. Periodic review of this manual and symposia similar to the one held in New Orleans in 1999 provide a greater focus and heighten the interest of the oceanographic community to continuous improvements. In the original Handbook the following word of caution was made. It remains germane. It is appropriate to insert a word of caution for the reader who is dealing with the evaluation of a winch and wire system. That caution is that in dealing with a calculated ideal it may not always be possible to achieve that ideal in practice due to the physical restraints that are imposed by research vessel size and configuration. When it becomes necessary to depart from the calculated ideal for one reason or the other, the assessment should be scrutinized carefully in order to define the true operational limits for the equipment at hand. Additionally, problems that manifest themselves in an existing winch and wire system are rarely the result of a single element and are usually the result of several component problems. When problems do arise, the entire system should be evaluated and appropriate corrective or de-rating measures taken. This handbook contains information suitable to initiate a careful review of existing winch systems as well as being useful for the specification of upgrades or new systems. It is the hope of the authors that this handbook will serve as a ready reference for both the oceanographic and commercial communities, now and in the future.

Submarine cable infrastructure is crucial for global telecommunications, supporting international data transfer and internet connectivity. As the demand for high-capacity and resilient networks grows, the need for a comprehensive understanding of research trends and developments in this field becomes more important. However, a systematic review of the academic literature on submarine cable infrastructure remains scarce. This bibliometric review aims to address this gap by analyzing the evolution of research on submarine cables and their technological, economic, and regulatory aspects. Data was collected from Scopus using advanced search queries with the keywords “submarine,” “cables,” “fiber,” and “fibre,” yielding a final dataset of 1,989 documents. Statistical analysis and graph generation were conducted using Scopus Analyzer, while OpenRefine was utilized for data cleaning and harmonization. VOSviewer was then employed for data visualization to identify key research clusters, co-authorship patterns, and emerging trends. The analysis reveals a significant increase in research output over the past decade, with notable contributions from leading countries, including the United States, the United Kingdom, and China. Key thematic areas include advances in cable technology, network resilience, and the economic and regulatory challenges of deploying submarine cables. This bibliometric review offers valuable insights into the structure and dynamics of the field, highlighting key areas for future research and offering a foundational reference for stakeholders in the submarine cable industry.

The maximum emergency operating temperatures of extruded dielectric cables were established several years ago and need re-evaluation vis-a-vis the materials and cable technology now available. A research program was undertaken with the objective of determining satisfactory limits of operation at elevated temperatures of extruded materials and cable constructions. This work focuses on the study of the temperature behavior of polymer materials used in conventional extruded cables. An extensive study has been made of the electrical, mechanical, thermal, and physico-chemical behavior of extruded dielectric materials as a function of temperature. Materials studied included XLPE, filled XLPE, EPR compounds and semiconducting XLPE, and data was obtained on specimens cut from full size extruded cables as well as laboratory molded specimens. Measurements of ac and impulse breakdown strength, ac loss and dielectric constant, dc resistivity, corona degradation; of mechanical properties such as tensile and compressive creep, bearing strength, hardness, thermal conductivity and thermal expansion; and of various physio-chemical properties, were performed over a range of temperatures extending from 25/sup 0/C to well above the present emergency operating temperatures. The results are presented in a form that emphasizes differences and similarities between the behavior of XLPE and EPR materials at elevated temperatures. The use of those materials at elevated temperatures is discussed with regard to satisfactory cable operation under emergency conditions.

The International Electrotechnical Commission Technical Committee 86 (IEC TC 86) is a standards development organization that prepares and decides on international standards in relation to products used for optical fiber communication.In this article, we provide an overview of standardization activities, introduce topics discussed at meetings in 2019 and 2020, and describe the Japanese standardization strategy in IEC TC 86.

The benefits of utilizing energy exchange between the Norwegian hydroelectric power system and the thermal power systems in Europe make it interesting to establish new HVDC sea cable interconnections. Providing the required licenses are issued by the national authorities involved, several new HVDC links may be established from the southern part of Norway to the continent each having a cable length of approximately 550 km. A total power of 3000 MW or more can then be exchanged through the HVDC links including the existing Skagerrak interconnection. It is planned to transmit a maximum power of 600 MW or even 800 MW, by each new HVDC link at a DC voltage of 500 kV assuming that progress in cable technology allows this voltage level in the coming years. A feasibility study with detailed modelling of all HVDC interconnections, the AC system of Southern Norway and relevant parts of the UCPTE system has been carried out. Especially the close electrical proximity between the converter stations in Norway (the distance between the converter stations is 40-60 km) requires detailed studies using digital simulation. In the following the advantages of energy interchange, technical aspects and the main results of the system dynamic study are discussed.

The problems of technique and equipment used in the crosslinking of polyethylene polymer are discussed. The practice of organosilicon chemistry for crosslinking of polyethylene chains is also considered. The use of a Cavity Transfer Mixer (CTM) for control of silane‐based crosslinking is described and the properties of the resultant polymers are tested. Use of this crosslinking method via the CTM produces polyethylene with improved hot‐water characteristics.

ALTHOUGH important problems in the field of cable engineering require the determination of transient temperatures of cables, the rather formidable mathematics involved in a rigorous solution discourages many engineers from attempting these calculations. Thus, comparatively fewengineers are familiar with the methods of solving such problems. Since the ability to handle transient temperature calculations is necessary both in the determination of short-time overload ratings and in the design of oil-filled cable lines, this subject should be mastered by cable engineers employed by utility companies. A new method of solving the transient temperature and oil demand problems of 3-conductor cables is particularly stressed.

Electron beams in cable engineering