Research on the mechanical–electrical properties is crucial for designing and preparing high-temperature superconducting(HTS)cables.Various winding core structures can influence the mechanical–electrical behavior of...Research on the mechanical–electrical properties is crucial for designing and preparing high-temperature superconducting(HTS)cables.Various winding core structures can influence the mechanical–electrical behavior of cables,but the impact of alterations in the winding core structure on the mechanical–electrical behavior of superconducting cables remains unclear.This paper presents a 3D finite element model to predict the performance of three cables with different core structures when subjected to transverse compression and axial tension.The three cables analyzed are CORC(conductor-on-round-core),CORT(conductor-on-round-tube),and HFRC(conductor-on-spiral-tube).A parametric analysis is carried out by varying the core diameter and inner-to-outer diameter ratio.Results indicate that the CORT cable demonstrates better performance in transverse compression compared to the CORC cable,aligning with experimental data.Among the three cables,the HFRC cables exhibit the weakest resistance to transverse deformation.However,the HFRC cable demonstrates superior tensile deformation resistance compared to the CORT cable,provided that the transverse compression properties are maintained.Finite element results also show that the optimum inner-to-outer diameter ratios for achieving the best transverse compression performance are approximately 0.8 for CORT cables and 0.6 for HFRC cables.Meanwhile,the study explores the effect of structural changes in HTS cable winding cores on their electromagnetic properties.It recommends utilizing small tape gaps,lower frequencies,and spiral core construction to minimize eddy losses.The findings presented in this paper offer valuable insights for the commercialization and practical manufacturing of HTS cables.展开更多
A new method is developed for removing the nickel coating on ITER superconducting cables by mechanical polishing.The obvious advantage of the mechanical method,which uses a nylon brush,is that there is no chemical res...A new method is developed for removing the nickel coating on ITER superconducting cables by mechanical polishing.The obvious advantage of the mechanical method,which uses a nylon brush,is that there is no chemical residual left in the cable,which would otherwise result in passive effects on the joint resistance.The coating resistance test results of this newly developed method are compared with those of the two other methods that can meet the requirements of ITER.An automatic polishing machine is designed and manufactured for the procedure to provide quality under precise control.This new technique can replace the conventional manual method due to its improved efficiency.展开更多
In an integrated structure low resistance CICC joint, current is conducted by outer cable strands coming into touch with the conductive Cu sole. So it is an important condition for satisfying joint performance that ea...In an integrated structure low resistance CICC joint, current is conducted by outer cable strands coming into touch with the conductive Cu sole. So it is an important condition for satisfying joint performance that each strand of the cable inside the joint is able to come to the outermost by transposition. This paper presents analysis, calculation and figures for the strand transposition. According to the twist procedures of the superconducting cable, the author computed the actual pitch of each stage cable, consecutively computed the projection of each stage cable on the axis of the cable (z axis) and the corresponding twist angle as the z coordinate changes, which is then drawn by AutoCAD. From the results shown in the figures, the minimal cable length, which enables each strand to transpose almost equally to the outermost of the cable in such a length, call be determined as the optimal joint length.展开更多
A 33.5 m, 35 kV/121 MVA, three-phase, warm dielectric HTS power cable system was successfully installed and activated in China Southern Power Grid at the Puji substation in Kunming on April 19th of 2004, supplying ele...A 33.5 m, 35 kV/121 MVA, three-phase, warm dielectric HTS power cable system was successfully installed and activated in China Southern Power Grid at the Puji substation in Kunming on April 19th of 2004, supplying electricity to four industrial customers （including two metallurgical refineries） and a residential population of about 100000. In this paper, we give an update on the operation and maintenance status of the system and comments on reliability issues. We conclude that the superconducting cable system is currently quite robust and feasible for particular utility applications, and it will be improved by advancement in cryogenic equipment and system technology.展开更多
In December 2021,the 35-kV kilometer-level high-temperature superconducting(HTS)demonstration cable was officially connected to the grid in Xuhui District,Shanghai,China.A three-in-one HTS cable with a rated current o...In December 2021,the 35-kV kilometer-level high-temperature superconducting(HTS)demonstration cable was officially connected to the grid in Xuhui District,Shanghai,China.A three-in-one HTS cable with a rated current of 2.2 kA,which replaces four-parallel lines XLPE cables,has been used in this project.This cable powers one of the busiest districts of Shanghai and serves to demonstrate and study the stability and reliability of a superconducting cable in the municipal power system.This project officially started in February 2019,and the type test of the prototype cable system was completed in November 2019.The commissioning test will be completed in November 2021.This paper introduces the main operating parameters,relevant research studies,and tests of this project.展开更多
Cables composed of rare-earth barium copper oxide(REBCO)tapes have been extensively used in various superconducting devices.In recent years,conductor on round core(CORC)cable has drawn the attention of researchers wit...Cables composed of rare-earth barium copper oxide(REBCO)tapes have been extensively used in various superconducting devices.In recent years,conductor on round core(CORC)cable has drawn the attention of researchers with its outstanding current-carrying capacity and mechanical properties.The REBCO tapes are wound spirally on the surface of CORC cable.Under extreme loadings,the REBCO tapes with layered composite structures are vulnerable,which can lead to degradation of critical current and even quenching of superconducting devices.In this paper,we simulate the deformation of CORC cable under external loads,and analyze the damage inside the tape with the cohesive zone model(CZM).Firstly,the fabrication and cabling of CORC are simulated,and the stresses and strains generated in the tape are extracted as the initial condition of the next step.Then,the tension and bending loads are applied to CORC cable,and the damage distribution inside the tape is presented.In addition,the effects of some parameters on the damage are discussed during the bending simulations.展开更多
Currently,IEC/TC90 is working on standardizing the method for measuring critical current(Ic)in superconducting cables.At the end of 2020,an international round robin test(RRT)was organized,in which five Chinese instit...Currently,IEC/TC90 is working on standardizing the method for measuring critical current(Ic)in superconducting cables.At the end of 2020,an international round robin test(RRT)was organized,in which five Chinese institutions participated,and four accomplished the test.The electric-field versus current(E-I)curves obtained by each institution are highly repeatable.Those obtained by different institutions are nearly identical after appropriate curve averaging,indicating high reproducibility,except the last participant's inner core curves.The discrepancy was later determined to be the result of sample cable damage.After excluding highly deviated data,it is determined that the maximum relative standard uncertainty in I_(c) is 0.7%,and the maximum relative standard uncertainty in n-value is 12.8%.The I_(c)values are comparable to Japan's domestic RRT results,but the n-values are significantly different.The test results support the DC four-terminal method as a recommended test method,with a target relative uncertainty of less than 2%for the Ic value.展开更多
In this paper, the design optimization of the structural parameters of multilayer conductors in high temperature superconducting （HTS） cable is reviewed. Various optimization methods, such as the particle swarm opti...In this paper, the design optimization of the structural parameters of multilayer conductors in high temperature superconducting （HTS） cable is reviewed. Various optimization methods, such as the particle swarm optimization （PSO）, the genetic algorithm （GA）, and a robust optimization method based on design for six sigma （DFSS）, have been applied to realize uniform current distribution among the multilayer HTS conductors. The continuous and discrete variables, such as the winding angle, radius, and winding direction of each layer, are chosen as the design parameters. Under the constraints of the mechanical properties and critical current, PSO is proven to be a more powerful tool than GA for structural parameter optimization, and DFSS can not only achieve a uniform current distribution, but also improve significantly the reliability and robustness of the HTS cable quality.展开更多
基金supported by the National Natural Science Foundation of China(12072136).
文摘Research on the mechanical–electrical properties is crucial for designing and preparing high-temperature superconducting(HTS)cables.Various winding core structures can influence the mechanical–electrical behavior of cables,but the impact of alterations in the winding core structure on the mechanical–electrical behavior of superconducting cables remains unclear.This paper presents a 3D finite element model to predict the performance of three cables with different core structures when subjected to transverse compression and axial tension.The three cables analyzed are CORC(conductor-on-round-core),CORT(conductor-on-round-tube),and HFRC(conductor-on-spiral-tube).A parametric analysis is carried out by varying the core diameter and inner-to-outer diameter ratio.Results indicate that the CORT cable demonstrates better performance in transverse compression compared to the CORC cable,aligning with experimental data.Among the three cables,the HFRC cables exhibit the weakest resistance to transverse deformation.However,the HFRC cable demonstrates superior tensile deformation resistance compared to the CORT cable,provided that the transverse compression properties are maintained.Finite element results also show that the optimum inner-to-outer diameter ratios for achieving the best transverse compression performance are approximately 0.8 for CORT cables and 0.6 for HFRC cables.Meanwhile,the study explores the effect of structural changes in HTS cable winding cores on their electromagnetic properties.It recommends utilizing small tape gaps,lower frequencies,and spiral core construction to minimize eddy losses.The findings presented in this paper offer valuable insights for the commercialization and practical manufacturing of HTS cables.
基金supported by ITER Research Project of China Matched Program(No.2008GB102000)
文摘A new method is developed for removing the nickel coating on ITER superconducting cables by mechanical polishing.The obvious advantage of the mechanical method,which uses a nylon brush,is that there is no chemical residual left in the cable,which would otherwise result in passive effects on the joint resistance.The coating resistance test results of this newly developed method are compared with those of the two other methods that can meet the requirements of ITER.An automatic polishing machine is designed and manufactured for the procedure to provide quality under precise control.This new technique can replace the conventional manual method due to its improved efficiency.
文摘In an integrated structure low resistance CICC joint, current is conducted by outer cable strands coming into touch with the conductive Cu sole. So it is an important condition for satisfying joint performance that each strand of the cable inside the joint is able to come to the outermost by transposition. This paper presents analysis, calculation and figures for the strand transposition. According to the twist procedures of the superconducting cable, the author computed the actual pitch of each stage cable, consecutively computed the projection of each stage cable on the axis of the cable (z axis) and the corresponding twist angle as the z coordinate changes, which is then drawn by AutoCAD. From the results shown in the figures, the minimal cable length, which enables each strand to transpose almost equally to the outermost of the cable in such a length, call be determined as the optimal joint length.
基金This work was supported in part by the Chinese Ministry of Science and Technology under Grant No. 2002AA306154, 2004AA306110,2005AA306120 and 2006AA03Z207the Beijing Municipal Scienceand Technology Commission under Grant No. H020420010210the Yunnan Provincial Science and Technology Department under Grant No.2003BABCA05A041 and 2003530101000415.
文摘A 33.5 m, 35 kV/121 MVA, three-phase, warm dielectric HTS power cable system was successfully installed and activated in China Southern Power Grid at the Puji substation in Kunming on April 19th of 2004, supplying electricity to four industrial customers （including two metallurgical refineries） and a residential population of about 100000. In this paper, we give an update on the operation and maintenance status of the system and comments on reliability issues. We conclude that the superconducting cable system is currently quite robust and feasible for particular utility applications, and it will be improved by advancement in cryogenic equipment and system technology.
文摘In December 2021,the 35-kV kilometer-level high-temperature superconducting(HTS)demonstration cable was officially connected to the grid in Xuhui District,Shanghai,China.A three-in-one HTS cable with a rated current of 2.2 kA,which replaces four-parallel lines XLPE cables,has been used in this project.This cable powers one of the busiest districts of Shanghai and serves to demonstrate and study the stability and reliability of a superconducting cable in the municipal power system.This project officially started in February 2019,and the type test of the prototype cable system was completed in November 2019.The commissioning test will be completed in November 2021.This paper introduces the main operating parameters,relevant research studies,and tests of this project.
基金Project supported by the National Natural Science Foundation of China(Nos.U2241267,1217215511872195)。
文摘Cables composed of rare-earth barium copper oxide(REBCO)tapes have been extensively used in various superconducting devices.In recent years,conductor on round core(CORC)cable has drawn the attention of researchers with its outstanding current-carrying capacity and mechanical properties.The REBCO tapes are wound spirally on the surface of CORC cable.Under extreme loadings,the REBCO tapes with layered composite structures are vulnerable,which can lead to degradation of critical current and even quenching of superconducting devices.In this paper,we simulate the deformation of CORC cable under external loads,and analyze the damage inside the tape with the cohesive zone model(CZM).Firstly,the fabrication and cabling of CORC are simulated,and the stresses and strains generated in the tape are extracted as the initial condition of the next step.Then,the tension and bending loads are applied to CORC cable,and the damage distribution inside the tape is presented.In addition,the effects of some parameters on the damage are discussed during the bending simulations.
基金the Strategic Priority Research Program of Chinese Academy of Sciences,Grant No.XDB 2500.
文摘Currently,IEC/TC90 is working on standardizing the method for measuring critical current(Ic)in superconducting cables.At the end of 2020,an international round robin test(RRT)was organized,in which five Chinese institutions participated,and four accomplished the test.The electric-field versus current(E-I)curves obtained by each institution are highly repeatable.Those obtained by different institutions are nearly identical after appropriate curve averaging,indicating high reproducibility,except the last participant's inner core curves.The discrepancy was later determined to be the result of sample cable damage.After excluding highly deviated data,it is determined that the maximum relative standard uncertainty in I_(c) is 0.7%,and the maximum relative standard uncertainty in n-value is 12.8%.The I_(c)values are comparable to Japan's domestic RRT results,but the n-values are significantly different.The test results support the DC four-terminal method as a recommended test method,with a target relative uncertainty of less than 2%for the Ic value.
文摘In this paper, the design optimization of the structural parameters of multilayer conductors in high temperature superconducting （HTS） cable is reviewed. Various optimization methods, such as the particle swarm optimization （PSO）, the genetic algorithm （GA）, and a robust optimization method based on design for six sigma （DFSS）, have been applied to realize uniform current distribution among the multilayer HTS conductors. The continuous and discrete variables, such as the winding angle, radius, and winding direction of each layer, are chosen as the design parameters. Under the constraints of the mechanical properties and critical current, PSO is proven to be a more powerful tool than GA for structural parameter optimization, and DFSS can not only achieve a uniform current distribution, but also improve significantly the reliability and robustness of the HTS cable quality.
