High-temperature superconducting cable
July 17, 2007 Figure 1, the basic structure of heat insulation cable schematic 1. High-temperature superconducting cable profile High-temperature superconducting power transmission cable according to the form of AC and DC can be divided into two types; Are classified according to their structural characteristics, electrical insulation materials under different operating temperature, divided Thermal insulation or temperature superconducting cable insulation (WD) and cold insulated superconducting cable (CD). Thermal insulation of electrical insulation layer superconducting cables and conventional power cable insulation is similar to work at room temperature (Figure 1); ColdMargin of superconducting cables electrical insulation work in the low temperature of liquid nitrogen, higher demands on insulation material (Figure 2). Of course, can also be classified according to conventional power cables are divided into single-phase cable and multi-phase cable. Thermal insulation The basic structure of superconducting cable, from the inside out, as follows: Tubular supports (usually corrugated pipe, which through liquid nitrogen); Superconducting conductor layer (the layer wound superconducting tapes); Thermal insulation layer (for the vacuum insulation kit); Conventional electrical insulation layer (work at room temperature); ElectricityShielding layer and protective layer (similar to conventional power cable). Figure 1. Figure 2 in which the basic structure diagram of cable insulation Cold insulated superconducting cable's basic structure, from inside to outside, as follows: Tubular supports (within the pass liquid nitrogen); Superconducting conductor layer (as the cable carrying conductors); Electrical insulation layer (work in liquid nitrogen at low temperature); Superconducting shielding layer (for superconducting tapes wound); Return level of liquid nitrogen (with tubular supports composition of liquid nitrogen reflux liquid nitrogen within the cycle); Thermal insulation layer (for the vacuum insulation kit); Conventional cable shield and sheath. Figure 2. Terminal (Termination) is a high-temperature superconducting cable structure, an important component of HTS cables and other electrical equipment outside the connection between the port and also the cooling medium and cooling equipment, cable connection port, to carry out the transition temperature and electric potential. The structure of the terminal and the cable supporting the structures, cold insulation of cables, as more layer of superconducting shielding layer and back layer of liquid nitrogen, the structure more complex, but the basic structure shown in Figure 3. Superconducting cable conductor layer and the bulk metal in liquid nitrogen under conventional connection (SC-NC connection), then by the conventional metal (current head) leads to the transition from the liquid nitrogen temperature to room temperature, current head of the dimensions are designed in order to thermal transition temperature uniformity and overall minimum. End of the heat insulation structure will minimize the heat leak; electrical insulation to ensure the current head of the insulation strength and liquid nitrogen from the ground potential (cooling system) to high potential (cable terminal) transition. Figure 3, the basic structure of superconducting cable termination First, the discovery of superconductivity The late 19th century, due to the application of electric
