| The ever-increasing demand of electric power results in raising levels of the short current, this means power apparatus have to be confronted with higher electromagnetic force and thermal effect during fault states. As a consequence, exorbitant short current will destroy power system and menace the security for personnel working near power equipment. For lowering the short-current to the level that the control equipment of power system can break, people have to sometimes partition power system, or adopt some measure to limit short current, such as making use of air core reactor, thermosensitive resistor, high-impedance transformer, or GTO equipment, however, anyone of them will bring the system negative influence or exist circumscription of use field. One of the most promising innovative limiting current device is superconducting fault current limiter (SCFCL) which use the special characteristics of superconductor. In a normal work condition, it is a good conductor with no influence on power system. However, in the case of short-circuiting, its impedance abruptly increase to limit short current because superconductor transit to resistive state from zero resistive state by being quenched after the fault current exceeds the critical value. It works naturally and is self-examination, self-triggered, self-operation and self-restore. If its product can be become turn, not only lower specifications of protection equipment or upgrade the capability of the existing electrical transmission system, but also can exalt the safe and dependability of the power system and power supply quantity.This paper introduced firstly superconductor's basic characteristic and its theory, discussed its application. Then reviewed the development of the superconducting fault current limiter, mainly about their principles, configurations and characteristics of SCFCL. the system requirements for the current limiting devices have been proposed and potential installation locations and benefits for user resulting from the effective fault current limiter have been shown. Adopting present worthy analysis measure of engineering economics, analyzed quantitatively the economic benefit of SCFCL, and expatiated the technique benefits of SCFCL from the dependable with lower system insulate level. Later, the magnetic-shield inductive SCFCL, 3-phase reactor SCFCL and saturated iron core SCFCL are studied.The magnetic-shield SCFCL which mainly consists of a copper coil, asuperconducting tube and an iron core .In normal operation ,the SCFCL has low impedance because the superconducting tube shield the iron core .During fault conditions the magnetic field penetrates the core resulting in a large impedance. The PSPICE simulating circuit of this SCFCL was constructed and simulations of short-current limiting performance of one prototype were carried out, the results are in good agreement with the test results of literature. Additionally, the effect of parameters of this SCFCL on limiting characteristic has been studied through computer simulation.The 3-phase reactor SCFCL consists of three superconducting windings with the same number of turns, which are wound on a single iron core. In a normal condition, it is a good conductor with no impedance because the flux is zero in the iron core. However, in single-line-to-ground fault, it becomes a reactor with large inductance suppressing the fault current, Further more, for two or three-phase short circuit, the reactance of the SCFCL keep zero but it is good for limiting the fault current by the abruptly increasing resistance of the superconducting winding. In this paper, analyzing characteres of 3-phase current, equivalent impedances of 3-phase reactor superconducting fault current limiter have been concluded under every operating condition, and its equivalent circuit has been constructed. The simulation results demonstrate that the theoretical analyses on this SCFCL is true.The saturated iron core SCFCL consists of a pair of magnetic cores (for single phase) with A...
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