Development of a new 6.6 kV/ 1500 A class superconducting fault current limiter for electric power systems

A superconducting current limiter comprising a noninductively wound AC superconducting coil (trigger coil) connected in parallel with a limiting coil was developed. A model electric power system for the application of this type of superconducting current limiter was created, 400 V/100 A class model superconducting current limiters were fabricated, and various current limiting tests were performed with respect to short-circuit currents and phases varied over a wide range. The results demonstrate that the proposed current limiter possesses performance characteristics fully adequate for application to the model system. A 6.6 kV/1500 A class superconducting trigger coil was developed, with a scale permitting, in principle, validation tests of applicability to actual power systems. This coil was demonstrated to be capable of limiting short-circuit currents by a factor of 1/30, and was subjected to detailed evaluation of current-limiting characteristics.>