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
We report the temperature, magnetic field and time dependences of magnetization in advanced Ba122 superconducting tapes. The sample exhibits peculiar vortex creep behavior. Below 10 K, the normalized magnetization rel...We report the temperature, magnetic field and time dependences of magnetization in advanced Ba122 superconducting tapes. The sample exhibits peculiar vortex creep behavior. Below 10 K, the normalized magnetization relaxation rate S = d ln(-M)/d ln(t) shows a temperature-insensitive plateau with a value comparable to that of low-temperature superconductors, which can be explained within the framework of collective creep theory. It then enters into a second collective creep regime when the temperature increases. Interestingly, the relaxation rate below 20 K tends to reach saturation with increasing the field. However, it changes to a power law dependence on the field at a higher temperature. A vortex phase diagram composed of the collective and the plastic creep regions is shown. Benefiting from the strong grain boundary pinning, the advanced Bal22 superconducting tape has potential to be applied not only in liquid helium but also in liquid hydrogen or at temperatures accessible with cryocoolers.展开更多
Ag-sheathed BiPbSrCaO(2223)superconducting tapes prepared by the powder-in-tube technique were inVeSgated. The Mswt of M layCr and the Jc at 77 K are spengly dspendent on the amouDt of cold wotheg and annchg condition...Ag-sheathed BiPbSrCaO(2223)superconducting tapes prepared by the powder-in-tube technique were inVeSgated. The Mswt of M layCr and the Jc at 77 K are spengly dspendent on the amouDt of cold wotheg and annchg condition. The Jc bo by uhahal tw aha drawing and rolling. The OPbown annwtg theperawt, boe and coohag de tO madrihe Jc vaiueS were in the range 84()-- 850t, 1bo^2bo h and 50-- loot / h, nyhvejy. The mndum tuSPOrt Jt at 77 K under zero mopetic field was l.33 x l04 A / cm2.展开更多
Owing to the high performance, the second generation （2 G） high Tc superconducting tapes based on yttrium barium copper oxide have attracted much attention of the researchers worldwide to develop the processing tech...Owing to the high performance, the second generation （2 G） high Tc superconducting tapes based on yttrium barium copper oxide have attracted much attention of the researchers worldwide to develop the processing techniques for application. In recent years, a series of the achievements have made the 2 G tapes become the focus of the superconductor research. An overview of the recent progress of 2 G superconductor tapes was provided,展开更多
The microstructures of the YBCO composited superconducting tapes with different J_c were analysed by TEM.The relationship between microstructure and J_c of the tapes is discussed in detail.It is demonstrated that J_c ...The microstructures of the YBCO composited superconducting tapes with different J_c were analysed by TEM.The relationship between microstructure and J_c of the tapes is discussed in detail.It is demonstrated that J_c value of the tapes increases significantly with the decrease in the width of grain boundary,increase of the twin density and the reducing of the amount of precipitates at grain boundary.At grain boundary of the tapes,howev- er,small amount of non-superconducting phases can-not be avoided.For the fabrication of high J_c YBCO com- posited tapes,it is very important to improve the microstructure of the superconductor perfectly.展开更多
Bi-2223 precursor powders are prepared by both oxalate co-precipitation(CP) and spray pyrolysis(SP) methods.The influence of fabrication methods on the superconducting properties of Bi-2223 tapes are systematically st...Bi-2223 precursor powders are prepared by both oxalate co-precipitation(CP) and spray pyrolysis(SP) methods.The influence of fabrication methods on the superconducting properties of Bi-2223 tapes are systematically studied. Compared to the CP method, SP powder exhibits spherical particle before calcination and smaller particle size after calcinations with more uniform chemical composition, which leads to a lower reaction temperature during calcination process for Bi-2223 tapes. Meanwhile, the non-superconducting phases in SP powder are more uniformly distributed with smaller particle sizes. These features result in finer homogeneity of critical current in large-length of Bi-2223 tape, higher density of filaments and better texture after heat treatment. Therefore,the SP method could be considered as a better route to prepare precursor powder for large-length Bi-2223 tape fabrication.展开更多
In this paper, 2201 and 2212 phases as the corresponding precursor of forming 2212 and 2223 phases are discussed,and the constructive process of unit cell of 2201 phase is ascertained by XRD and chemical kinetics me...In this paper, 2201 and 2212 phases as the corresponding precursor of forming 2212 and 2223 phases are discussed,and the constructive process of unit cell of 2201 phase is ascertained by XRD and chemical kinetics method. Subsequently, the process of 221展开更多
Highly textured (Bi,Pb)2Sr2Ca2Cu3Ox superconducting tapes have been fabricated by means of magnetic-field and vibration technique. This method is an effective way of improving the degree of grain alignment and density...Highly textured (Bi,Pb)2Sr2Ca2Cu3Ox superconducting tapes have been fabricated by means of magnetic-field and vibration technique. This method is an effective way of improving the degree of grain alignment and density of oxide core in tapes after heat treatment and pressing cycles.Jc of above 20% was increased than that without treatment.展开更多
Ag-sheathed(Bi,Pb)_2Sr_2Ca_2Cu_3O_x tapes were fabricated by a powder-in-tube method.A high critical current density of 2.8×10~4 A/cm^2 at 77K,0T and 4×10~4 A/cm^2 at 4.2K,5T(H⊥ab),6.3× 10~4 A/cm^2 at ...Ag-sheathed(Bi,Pb)_2Sr_2Ca_2Cu_3O_x tapes were fabricated by a powder-in-tube method.A high critical current density of 2.8×10~4 A/cm^2 at 77K,0T and 4×10~4 A/cm^2 at 4.2K,5T(H⊥ab),6.3× 10~4 A/cm^2 at 4.2K,7T(H∥ab)is obtained.The microstructure of the tapes with high J_c values was in- vestigated by transmission electron microscope(TEM)and X-ray energy dispersive spectrum system(EDS). For comparison,a tape fabricated by a different procedure with a low J_c of about 1×10~4 A/cm^2 at 77K,0T was also studied.The relationship between J_c and microstructure of the tapes and the effect of the processing on the microstructure and J_c were elucidated.展开更多
INTRODUCTIONIn order to improve the efficiency of the electrically small antenna, which has the physical extension smaller than the maximum free space wavelength transmitted or received, superconducting materials bega...INTRODUCTIONIn order to improve the efficiency of the electrically small antenna, which has the physical extension smaller than the maximum free space wavelength transmitted or received, superconducting materials began to be utilized in fabricating antennas since 1960s. In 1988, the Birmingham group of UK made for the first time the small dipole antennas展开更多
This paper aims to briefly review the phenomenal role of superconductivity in wide ranging cable technological applications.HTS(high temperature superconducting)cable applications proved to expand a diverse range of e...This paper aims to briefly review the phenomenal role of superconductivity in wide ranging cable technological applications.HTS(high temperature superconducting)cable applications proved to expand a diverse range of economic and technical viability within electric transmission.HTS cable technology proved to attain low loss power transmission along with large electric power capacity that comes with great benefits:energy conservation,carbon dioxide reduction,resource preservation,and energy saving.Due to the following advantages,HTS cable power technology is widely promoted and readily constructed for implementation around the world.展开更多
Bi system tapes were prepared using the powder in tube method. The tapes were processed to their final thickness by repeated rolling and pressing and by a combination of rolling and pressing with intermediate heat tre...Bi system tapes were prepared using the powder in tube method. The tapes were processed to their final thickness by repeated rolling and pressing and by a combination of rolling and pressing with intermediate heat treatment. The different processing techniques greatly affected the critical current density J c of the tapes because the homogeneity of the ceramic core and the propensity for crack formation within the tapes mainly depended on the deformation process.展开更多
A hybrid energy transmission pipeline is proposed with the aim of long-distance cooperative transmission of electricity and chemical fuels, which is composed of an inner high-temperature superconducting (HTS) power ca...A hybrid energy transmission pipeline is proposed with the aim of long-distance cooperative transmission of electricity and chemical fuels, which is composed of an inner high-temperature superconducting (HTS) power cable and outer liquefied natural gas (LNG) pipeline. The flowing LNG could maintain the operating temperature of the inner HTS power cable within the range of 85 K-90 K, thus the Bi-2223 superconductors in the HTS power cable produce little Joule loss with the transmission current below the critical current. Owing to the advantages of high power density, low transmission losses and economical manufacturing costs, the hybrid energy transmission pipeline is expected to be widely utilized in the near future. In order to ensure the safety of the HTS power cable and explosive LNG in case of short-circuit faults, this paper tests and analyzes the characteristics of Bi-2223 HTS tapes of the Type HT-CA, Type HT-SS and Type H models under short-circuit current impacts at the LNG cooling temperature (85 K-90 K). An experimental platform is designed and established for the ampacity tests of HTS tapes above LN2 cooling temperature (77 K). The AC over-current impact tests at 85 K-90 K are carried out on each sample of Bi-2223 tapes respectively, and the experimental results are analyzed and compared to evaluate their performances under different operating conditions. The results indicate that the Type HT-CA tape can withstand 50 Hz short-circuit current impact with the amplitude of 1108 A (10 times of critical current Ic ) for 100 ms at 90 K, and its resistance is the smallest of the three tested samples under similar current impacts. Therefore, the Type HT-CA Bi-2223 tape is the optimal superconductor of the HTS power cable in the hybrid energy transmission pipeline.展开更多
The design progress of superconducting fault current limiter(SFCL)for transmission voltage is presented,with a focus on the results of recent key experiments that have led to a state‐of‐the‐art high‐voltage high‐...The design progress of superconducting fault current limiter(SFCL)for transmission voltage is presented,with a focus on the results of recent key experiments that have led to a state‐of‐the‐art high‐voltage high‐capacity super‐conducting current limiting techniques:the resistive alternating current(AC)SFCL,saturated iron cores AC SFCL,and resistive direct current(DC)SFCL.The main driving factors for designing SFCL in these projects are the preparation of high‐performance superconducting materials,the development of large‐scale superconducting current limiting winding,system testing,and operation technology.Based on the authors’experience with both AC and DC SFCLs,this paper focuses on the main design aspects of resistive SFCL at transmission voltage.The relationship between the hot spot caused by the inhomogeneity of long superconducting tape and the overall parameter selection is presented.In addition,the thermal calculation based on the current limiting resistance and a real‐time current curve is also proposed for the parameter design of the current limiting winding.展开更多
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Supported by the National Natural Science Foundation of China under Grant Nos 51402292 and 51677179the International Partnership Program of the Chinese Academy of Sciences under Grant Nos GJHZ1775 and 182111KYSB20160014+1 种基金the Key Research Program of Frontier Sciences of the Chinese Academy of Sciences under Grant No NoQYZDJ-SSW-JSC026the Strategic Priority Research Program of the Chinese Academy of Sciences under Grant No XDB25000000
文摘We report the temperature, magnetic field and time dependences of magnetization in advanced Ba122 superconducting tapes. The sample exhibits peculiar vortex creep behavior. Below 10 K, the normalized magnetization relaxation rate S = d ln(-M)/d ln(t) shows a temperature-insensitive plateau with a value comparable to that of low-temperature superconductors, which can be explained within the framework of collective creep theory. It then enters into a second collective creep regime when the temperature increases. Interestingly, the relaxation rate below 20 K tends to reach saturation with increasing the field. However, it changes to a power law dependence on the field at a higher temperature. A vortex phase diagram composed of the collective and the plastic creep regions is shown. Benefiting from the strong grain boundary pinning, the advanced Bal22 superconducting tape has potential to be applied not only in liquid helium but also in liquid hydrogen or at temperatures accessible with cryocoolers.
文摘Ag-sheathed BiPbSrCaO(2223)superconducting tapes prepared by the powder-in-tube technique were inVeSgated. The Mswt of M layCr and the Jc at 77 K are spengly dspendent on the amouDt of cold wotheg and annchg condition. The Jc bo by uhahal tw aha drawing and rolling. The OPbown annwtg theperawt, boe and coohag de tO madrihe Jc vaiueS were in the range 84()-- 850t, 1bo^2bo h and 50-- loot / h, nyhvejy. The mndum tuSPOrt Jt at 77 K under zero mopetic field was l.33 x l04 A / cm2.
文摘Owing to the high performance, the second generation （2 G） high Tc superconducting tapes based on yttrium barium copper oxide have attracted much attention of the researchers worldwide to develop the processing techniques for application. In recent years, a series of the achievements have made the 2 G tapes become the focus of the superconductor research. An overview of the recent progress of 2 G superconductor tapes was provided,
文摘The microstructures of the YBCO composited superconducting tapes with different J_c were analysed by TEM.The relationship between microstructure and J_c of the tapes is discussed in detail.It is demonstrated that J_c value of the tapes increases significantly with the decrease in the width of grain boundary,increase of the twin density and the reducing of the amount of precipitates at grain boundary.At grain boundary of the tapes,howev- er,small amount of non-superconducting phases can-not be avoided.For the fabrication of high J_c YBCO com- posited tapes,it is very important to improve the microstructure of the superconductor perfectly.
文摘Bi-2223 precursor powders are prepared by both oxalate co-precipitation(CP) and spray pyrolysis(SP) methods.The influence of fabrication methods on the superconducting properties of Bi-2223 tapes are systematically studied. Compared to the CP method, SP powder exhibits spherical particle before calcination and smaller particle size after calcinations with more uniform chemical composition, which leads to a lower reaction temperature during calcination process for Bi-2223 tapes. Meanwhile, the non-superconducting phases in SP powder are more uniformly distributed with smaller particle sizes. These features result in finer homogeneity of critical current in large-length of Bi-2223 tape, higher density of filaments and better texture after heat treatment. Therefore,the SP method could be considered as a better route to prepare precursor powder for large-length Bi-2223 tape fabrication.
文摘In this paper, 2201 and 2212 phases as the corresponding precursor of forming 2212 and 2223 phases are discussed,and the constructive process of unit cell of 2201 phase is ascertained by XRD and chemical kinetics method. Subsequently, the process of 221
文摘Highly textured (Bi,Pb)2Sr2Ca2Cu3Ox superconducting tapes have been fabricated by means of magnetic-field and vibration technique. This method is an effective way of improving the degree of grain alignment and density of oxide core in tapes after heat treatment and pressing cycles.Jc of above 20% was increased than that without treatment.
文摘Ag-sheathed(Bi,Pb)_2Sr_2Ca_2Cu_3O_x tapes were fabricated by a powder-in-tube method.A high critical current density of 2.8×10~4 A/cm^2 at 77K,0T and 4×10~4 A/cm^2 at 4.2K,5T(H⊥ab),6.3× 10~4 A/cm^2 at 4.2K,7T(H∥ab)is obtained.The microstructure of the tapes with high J_c values was in- vestigated by transmission electron microscope(TEM)and X-ray energy dispersive spectrum system(EDS). For comparison,a tape fabricated by a different procedure with a low J_c of about 1×10~4 A/cm^2 at 77K,0T was also studied.The relationship between J_c and microstructure of the tapes and the effect of the processing on the microstructure and J_c were elucidated.
文摘INTRODUCTIONIn order to improve the efficiency of the electrically small antenna, which has the physical extension smaller than the maximum free space wavelength transmitted or received, superconducting materials began to be utilized in fabricating antennas since 1960s. In 1988, the Birmingham group of UK made for the first time the small dipole antennas
文摘This paper aims to briefly review the phenomenal role of superconductivity in wide ranging cable technological applications.HTS(high temperature superconducting)cable applications proved to expand a diverse range of economic and technical viability within electric transmission.HTS cable technology proved to attain low loss power transmission along with large electric power capacity that comes with great benefits:energy conservation,carbon dioxide reduction,resource preservation,and energy saving.Due to the following advantages,HTS cable power technology is widely promoted and readily constructed for implementation around the world.
文摘Bi system tapes were prepared using the powder in tube method. The tapes were processed to their final thickness by repeated rolling and pressing and by a combination of rolling and pressing with intermediate heat treatment. The different processing techniques greatly affected the critical current density J c of the tapes because the homogeneity of the ceramic core and the propensity for crack formation within the tapes mainly depended on the deformation process.
基金supported by National Key R&D Project under Grant(2018YFB0904400).
文摘A hybrid energy transmission pipeline is proposed with the aim of long-distance cooperative transmission of electricity and chemical fuels, which is composed of an inner high-temperature superconducting (HTS) power cable and outer liquefied natural gas (LNG) pipeline. The flowing LNG could maintain the operating temperature of the inner HTS power cable within the range of 85 K-90 K, thus the Bi-2223 superconductors in the HTS power cable produce little Joule loss with the transmission current below the critical current. Owing to the advantages of high power density, low transmission losses and economical manufacturing costs, the hybrid energy transmission pipeline is expected to be widely utilized in the near future. In order to ensure the safety of the HTS power cable and explosive LNG in case of short-circuit faults, this paper tests and analyzes the characteristics of Bi-2223 HTS tapes of the Type HT-CA, Type HT-SS and Type H models under short-circuit current impacts at the LNG cooling temperature (85 K-90 K). An experimental platform is designed and established for the ampacity tests of HTS tapes above LN2 cooling temperature (77 K). The AC over-current impact tests at 85 K-90 K are carried out on each sample of Bi-2223 tapes respectively, and the experimental results are analyzed and compared to evaluate their performances under different operating conditions. The results indicate that the Type HT-CA tape can withstand 50 Hz short-circuit current impact with the amplitude of 1108 A (10 times of critical current Ic ) for 100 ms at 90 K, and its resistance is the smallest of the three tested samples under similar current impacts. Therefore, the Type HT-CA Bi-2223 tape is the optimal superconductor of the HTS power cable in the hybrid energy transmission pipeline.
基金supported in part by the National Key Research and Development Program under Grant 2017YFB0902300。
文摘The design progress of superconducting fault current limiter(SFCL)for transmission voltage is presented,with a focus on the results of recent key experiments that have led to a state‐of‐the‐art high‐voltage high‐capacity super‐conducting current limiting techniques:the resistive alternating current(AC)SFCL,saturated iron cores AC SFCL,and resistive direct current(DC)SFCL.The main driving factors for designing SFCL in these projects are the preparation of high‐performance superconducting materials,the development of large‐scale superconducting current limiting winding,system testing,and operation technology.Based on the authors’experience with both AC and DC SFCLs,this paper focuses on the main design aspects of resistive SFCL at transmission voltage.The relationship between the hot spot caused by the inhomogeneity of long superconducting tape and the overall parameter selection is presented.In addition,the thermal calculation based on the current limiting resistance and a real‐time current curve is also proposed for the parameter design of the current limiting winding.
