47results about How to "Increase the critical current" patented technology

The invention relates to a bismuth-series high-temperature superconducting wire component and a preparation method thereof. The superconducting wire component comprises at least two single superconducting wires with superconductivity, the width surfaces among the single superconducting wires are parallelly connected together in an electrical contact manner, and at least one metal reinforcing band is parallelly connected on the outer width surface of each of the two outermost superconducting wires in parallel connection. In order to further improve mechanical strength of the superconducting wire component, at least one metal coating with the mechanical strength higher than that of single metal reinforcing band is coated on the outer surface of the superconducting wire component. The superconducting wire component prepared by the method is high in mechanical strength and critical current.

The invention discloses an inductor and resistor compound superconducting reactor. The technical keys are that the superconducting reactor mainly comprises a superconducting inductive coil, a superconducting non-inductive coil, a low-temperature Dewar component, low-temperature insulating sleeves, superconducting binary current leads, superconducting transition leads and low-temperature refrigerant pipelines, wherein the superconducting inductive coil and the superconducting non-inductive coil are both completely soaked in low-temperature refrigerants inside the low-temperature Dewar component; the low-temperature insulating sleeves, the superconducting binary current leads and the low-temperature refrigerant pipelines are all connected with sealing cover plates of the low-temperature Dewar component; the superconducting inductive coil is connected in series with the superconducting non-inductive coil through the superconducting transition leads, and is connected with the superconducting binary current leads, so as to form the inductor and resistor compound superconducting reactor provided with a fixed inductance value and a variable resistance value. The superconducting reactor has the application characteristics of both the fixed inductance value of a single superconducting reactor and the variable resistance value of a single superconducting non-inductive coil, and can simultaneously have the current-limiting and power compensating function of an electric power system, as well as the high-efficient neutral point grounding function.

The invention provides a coil winding framework for improving the critical current of a superconducting coil and a winding method of the coil winding framework, wherein the framework comprises cover plates (1) and at least three winding frameworks; the superconducting coil is formed by winding a superconducting strip on the coil winding frameworks for improving the critical current of the superconducting coil; the cover plates (1) and the winding frameworks are detachably and sequentially arranged at intervals through a set mounting structure, namely, one cover plate (1) is detachably arrangedon the two sides of each winding framework; and the superconducting strip is wound on the winding frameworks to form the superconducting coil with a set shape structure. According to the coil windingframework, the vertical component of the magnetic field facing the strip can be effectively reduced, so that the critical current of the superconducting coil is improved, and a larger working currentvalue is provided for the superconducting coil; the usage amount of the superconducting strip can be reduced under the requirement that certain working current needs to be guaranteed, and the cost ofthe superconducting coil is lowered; and meanwhile, the overall magnetic field distribution generated by the superconducting coil cannot be influenced, and extra limitation is not caused to actual application of the superconducting coil.

The invention discloses a high-temperature superconducting twisted wire winding method. The winding method is characterized by comprising a step of strip cutting, wherein a high-temperature superconducting strip is cut into wire-shaped superconducting thin belts in a length direction; and a step of strip weaving, wherein the superconducting thin belts are weaved to form a new superconducting wire. According to the high-temperature superconducting twisted wire winding method, the macroscopic geometric structure of the superconducting strip is changed; the critical current of a superconducting magnet is improved in the application of the superconducting magnet; the alternating current loss is lowered, and the performance of the superconducting magnet is dramatically improved; and under the same condition, the cost for a user is equivalently reduced.

Method of producing superconducting cables by using cold plastic deformation operations only including the step of obtaining a bar-like semi-finished product of prefixed dimension through the steps of: forming round-section, mono- or multifilament, superconducting copper bars of relatively long length; assembling the bars about a cylindrical copper core of substantially the same length, using assembly templates, the templates having through holes arranged in a circle to support the bars, and a central through seat for supporting the core; tying the bars onto an outer lateral surface of the core; sliding onto one end of the bar/core assembly a number of metal supporting rings, while sliding the templates off the opposite end thereof; sliding a copper tube onto the bar/core assembly while cutting the ties in axial sequence and sliding off the supporting rings; and subjecting the assembly to a number of drawing operations.

The invention relates to a method for increasing the critical current of a single domain YBCO superconducting block, which belongs to the field of functional materials. The method is characterized by comprising the following steps: doping SiO2 nanometer powder of which the grain size is between 20 and 100 nanometers to pioneer powder of the single domain YBCO superconducting block; adding SiO2 nanometer powder which is 0.02 to 1 weight percent of the pioneer powder of the YBCO superconducting block to the pioneer powder; performing compression molding with a single shaft on the mixture after the mixture is mixed evenly through ball milling; and generating the single domain structured YBCO superconducting block by adopting a top seed assisted melt texture growth process (TSMTG). The process for preparing the SiO2 nanometer powder comprises the following steps: preparing a clear and transparent solution from tetraethyl orthosilicate, anhydrous ethanol and deionized water according to the volume ratio of 1 to 1-3 to 1-3, and forming a milky gel after water bath and stirring; and forming a dried gel and grinding the dried gel into fine powder, and baking the fine powder at a temperature of between 400 and 700 DEG C for 0.5 to 2.5 hours to obtain the SiO2 nanometer powder of which the grain size is between 20 and 100 nanometers. The method effectively increases the critical current the single domain YBCO superconducting block within a wide field range.

The invention relates to the technical field of yttrium barium copper oxide coating conductors, in particular to a high-performance REBCO multilayer film, application and a preparation method for the high-performance REBCO multilayer film. The high-performance REBCO multilayer film is composed of a REBCO thin film layer and an STO interlayer. The invention further relates to the application of the high-performance REBCO multilayer film during preparing of a high-temperature superconductive belt material and relates to the preparation method for the high-performance REBCO multilayer film. The preparation method comprises the following steps that an IBAD-MgO base belt plated with an isolated layer is taken, and the high-performance REBCO multilayer film is prepared through a multi-target multi-channel pulse laser method. The prepared high-performance REBCO multilayer film prepared has a pure C-axis orientation, a smooth compact surface and a high critical current density, and the critical current density reaches up to 5 MA/cm<2>. The REBCO multilayer film has high critical current under a self field or a magnetic field, has the high binding force, can meet the application requirements for a superconducting cable and the like and is suitable for industrialization production.

The invention discloses a method for manufacturing a REBCO superconducting film and a constant-temperature dip-coating device. The method comprises the following steps: (A) preparing a precursor solution containing rare earth element ions, barium ions, copper ions and a solvent; (b) controlling a coating temperature by a constant temperature way with the temperature not higher than 20 DEG C, controlling a substrate and the precursor solution to be at same set temperatures, and coating the precursor solution on the substrate to obtain a precursor film; and (c), placing the precursor film in a heat treatment furnace and carrying out thermal decomposition, sintering and oxygenation steps to obtain an REBCO superconducting film. According to the invention, the coating temperature is controlled to be at a specific constant value, so that the thickness of the film increases.

The invention belongs to the technical field of superconducting magnets, and particularly relates to a high-temperature superconducting magnet with a magnetic ring. In the high-temperature superconducting magnet with the magnetic ring, by a first silicon steel concentrating flux plate and a second silicon steel concentrating flux plate, a radial component of a leakage magnetic field at the end part of a high-temperature superconducting winding can be reduced, and critical current at the end part of the high-temperature superconducting winding can be increased; according to the high-temperature superconducting magnet, the number of parallel high-temperature superconducting tapes is not required to be increased, so that the problem of high rate of non-uniform current distribution and loop current between the parallel high-temperature superconducting tapes is solved; the structure of the high-temperature superconducting winding is not changed or a high-temperature superconducting material is not replaced, and the high-temperature superconducting magnet is applicable to high-temperature superconducting windings of a cross-over coil structure and a solenoid structure.

A Hall device manufacturing method and a Hall device are provided. A Hall device obtained by a Hall device manufacturing method directly photoetches an electrode pattern on a GaAs substrate surface and deposits a metal layer so that a metal material contacts with a two-dimensional electron gas structure layer to form a plurality of metal electrodes. Then, GaAs substrate prepared with multiple metal electrodes is annealed in shielding gas to form good ohmic contact between GaAs substrate surface and two-dimensional electron gas structure layer. Finally, the Hall device is cut out along the outside of the plurality of metal electrodes by a scriber. There is no Hall rod structure in Hall devices, which makes Hall devices have relatively large critical current. At the same time, the patternedmask layer enables accurate symmetry of the plurality of metal electrodes to be ensured when photolithography is performed. Moreover, the success rate of the ohmic contact resistance between the GaAssubstrate surface and the two-dimensional electron gas structure layer is 100% due to the reduction of the process steps of chemical etching of the Hall rod in the Hall device fabrication process.

The invention discloses a superconducting magnet comprising ferromagnetic rings. The superconducting magnet comprises a non-magnetic cylindrical framework, a superconducting solenoid coil and two annular cover plates, wherein one ferromagnetic ring is embedded on the surface, close to the superconducting solenoid coil, of each annular cover plate and is coaxial with the corresponding annular cover plate; one annular groove with a certain groove depth is formed in the surface, close to the superconducting solenoid coil, of each ferromagnetic ring, accordingly, an inner annular boss and an outer annular boss are formed on the inner edge and the outer edge of each ferromagnetic ring respectively, and the radial width between the inner annular boss and the outer annular boss is equal to the groove depth of each annular groove; the end surface of the superconducting solenoid coil is parallel to the bottom surface of the annular groove at the interval being the groove depth of each annular groove, and the numerical value of the interval between the inner edge of the end surface of the superconducting solenoid coil and the inner annular boss and the numerical value of the interval between the outer edge of the end surface of the superconducting solenoid coil and the outer annular boss are both equal to the groove depth of each annular groove. The critical current of the superconducting magnet is increased by attenuating the vertical magnetic-field component.

The disclosed method to improve critical current for a Bi-2223 belt material comprises: polishing the insulating varnish on selected area of the material with fine sand paper, cleaning, and using a dc constant power as electroplating source to output 3V voltage and alter plating time for different coating thickness. This invention can control ac loss fit to large-scale production.

The invention provides a low-voltage coil for a superconducting transformer. The low-voltage coil is formed by winding a superconducting strand with isotropic characteristics, the section of the superconducting strand is of a square structure, the superconducting strand is composed of a superconducting strand core with a square section and a metal wrapping layer, and the superconducting strand core is formed by stacking a plurality of superconducting tapes in a certain direction. According to the superconducting transformer adopting the isotropic superconducting strand to wind the low-voltagecoil, the situation that the current-carrying capacities of different positions of the superconducting coil are greatly different due to anisotropism of the current-carrying capacities of the superconducting strips under the action of an external magnetic field at present can be effectively improved, the current-carrying capacity of the superconducting tape is fully utilized, the critical currentof the superconducting coil is improved, the circulating current of a parallel circuit is reduced, and the economy, safety and stability of the superconducting transformer coil are improved.

The invention relates to a Fe (Se, Te) superconducting thick film and a preparation method and application thereof, and the preparation method of the Fe (Se, Te) superconducting thick film comprises the following steps: depositing a Fe (Se, Te) seed layer on a metal base band plated with a buffer layer by adopting a multi-channel pulse laser deposition method, and then depositing a plurality of Fe (Se, Te) superconducting layers on the Fe (Se, Te) seed layer. Compared with the prior art, the Fe (Se, Te) superconducting thick film prepared by the method has pure C-axis orientation, high superconducting transition temperature, high critical current and high critical current density, and under 4.2 K and self field, the critical current is greater than 300A, and the critical current density is as high as 2.3 MA/cm < 2 >; the Fe (Se, Te) superconducting thick film provided by the invention has high critical current and critical current density in a self field and a magnetic field, can meet high-intensity magnetic field application, and is suitable for industrial production.

The invention discloses a self-shielding cold-insulation direct-current high-temperature superconducting current-limiting cable which comprises a cooling channel, a cable skeleton, a semiconductor layer, a superconducting layer, an insulating layer and a protective layer. The cooling channel is located in the center of the cable skeleton, the semiconductor layer is arranged outside the cable skeleton, and a superconducting odd layer n is arranged outside the semiconductor layer; a superconducting even number layer 2n is arranged outside the superconducting odd number layer n, the semiconductorlayer and the insulating layer are sequentially arranged between the superconductive odd-number layer n and the superconductive even-number layer 2n from inside to outside, and the protective layer is arranged on the outermost superconducting layer. The current running directions of the superconductive odd-number layer n and the superconductive even-number layer 2n are opposite, and the strip winding directions are the same. The current running directions of the adjacent superconductive odd-number layer n and the superconductive even-number layer 2 (n + 1) are the same, and the strip windingdirections are opposite. The self-shielding cold-insulation direct-current high-temperature superconducting current-limiting cable of the scheme has the advantages of dual functions of transmission and current limiting, self-shielding and no electromagnetic interference, does not need to connect a superconducting current limiter, and enables the device cost and the operation and maintenance cost to be reduced.

The invention discloses a MgB2 superconducting cable joint. The MgB2 superconducting cable joint is of a round rod-shaped structure, the cross section structure of the MgB2 superconducting cable joint is that a central area is an Mg area, the central area is solid or hollow, and a B ring area, an Nb ring area and a Cu ring area which are of an annular structure are sequentially arranged around the periphery of the Mg area from the center to the outside; a plurality of connecting holes are formed in the B ring areas at the two ends of the MgB2 superconducting cable joint, the number of the connecting holes in each end face of the MgB2 superconducting cable joint is the same as the number of superconducting strands of the MgB2 superconducting cable needing to be connected to the end face, and the connecting holes are evenly distributed around the outer side of the Mg area. The invention also provides a preparation method and a connection method of the MgB2 superconducting cable joint. The superconducting cable joint disclosed by the invention has relatively high transportation performance. And the connected cable keeps a multi-strand structure and can be twisted for the second time, so that the alternating current loss of the superconducting cable joint is greatly reduced.