Superconducting power cable with enhanced superconducting core

Abstract

Enhanced superconducting power cable of at least one phase, characterized by two tubular sections, the first section being a flexible superconducting core, with a stainless steel tape mesh and copper tape layers overlaid at an angle of 0° to 45° followed by two or more superconducting material layers placed overlaid and a second application of two or more superconducting material layers in opposite direction with regard to the previous ones; the second tubular section is an annular space of vacuum thermal insulation formed by a flexible corrugated pipe covered with multilayer insulations, including also a pipe with a stainless steel mesh to adhere an internal semiconducting shield made of polyethylene with insulation followed by a second metal shield based on copper tapes and a polyethylene protecting cover.

1 . A superconducting power cable with enhanced superconducting core of al least one phase with cooling through nitrogen flow in the cavity of the central pipe, characterized because it has two tubular sections, being the first one a flexible superconducting core formed by a corrugated central pipe covered with a stainless steel tape mesh, layers of copper tapes overlaid at an application angle at 0° to 45°, two or more overlaid layers of superconducting material tapes with a cabling lay length of 2 to 300 cm and path angle between 0° to 45° to the right or left and then application of a second section of two or more superconducting materials layers applied in opposite direction to the path of the above mentioned layer section, being the previous assembly wrapped with an insulating material tape; the second tubular section is an annular space of vacuum thermal insulation protecting the central core and concentrically formed by a stainless steel flexible corrugated pipe as internal wall which is lined on the opposite wall with a multilayer thermal insulation, then said vacuum space is completed with a stainless steel corrugated additional pipe in the external wall of which stainless steel mesh is placed for the adherence of several layers; said several layers are formed by an internal semiconducting shield made of thermoplastic o thermosetting low density polyethylene, a polyethylene electric insulation, a second semiconducting shield, a metal shield made of copper tapes, and a polyethylene protecting cover.  
     
     
         2 . The superconducting power cable of  claim 1 , characterized because the first flexible corrugated pipe forming the vacuum annular space is made of 304 or 316 stainless steel and has an external diameter of 6 to 8 cm and an internal diameter of 4 to 5 cm, the corrugation depth can vary between 0.5 and 1 cm and the corrugation pitch is from 1 to 2 cm for a depth between 0.5 and 0.8 cm.  
     
     
         3 . The superconducting power cable of  claim 1 , characterized because the thermal insulation placed in several layers is an aluminum and mylar sheet 0.0005 to 0.005 cm thick.  
     
     
         4 . The superconducting power cable of  claim 1 , characterized because the second 304 or 316 stainless steel corrugated pipe has an external diameter between 8 and 10 cm and an internal diameter between 6 and 7 cm, with a corrugation depth between 0.5 and 1.5 cm, and a pitch between corrugations of 1 to 2 cm for a depth between 0.5 and 1 cm.  
     
     
         5 . The superconducting power cable of  claim 1 , characterized because the stainless steel mesh placed on the corrugated central pipe is placed in a braided way to form an external uniform flat surface.  
     
     
         6 . The superconducting power cables of  claim 1 , characterized because the first semiconducting shield is made of thermoplastic or thermosetting low density polyethylene, wherein the conductivity of this layer does no exceed 1000 Ω m at room temperature and has a thickness of al least 0.006 cm.  
     
     
         7 . The superconducting power cable of  claim 1 , characterized because the electric core insulation is based on thermoplastic or thermosetting or crossed chain low, medium or high density polyethylene and/or ethylene propylene, its thickness depending on the effect of the operation voltage on the cable and being between 0.229 and 0.976 cm.  
     
     
         8 . The superconducting power cable of  claim 1 , characterized because the second semiconducting shield is made of the same components as the first shield but its thickness is at least 0.0129 cm and its maximum volume resistivity is 500 Ω m at room temperature.  
     
     
         9 . The superconducting power cable of  claim 1 , characterized because the metal shield of cooper tape is 0.00635 cm thick, having a cross section area of at least 0.1 mm 2 /mm.  
     
     
         10 . The superconducting power cable of  claim 1 , characterized because the final protecting cover can be made of polyethylene o polyvinyl chloride (PVC), with a thickness between 0.203 and 0.279 cm.  
     
     
         11 . The superconducting power cable of  claim 1 , characterized because the vacuum thermal insulation system functions at temperatures of 77° K. and under a vacuum pressure of 10 mPa (milliPascal).