Development of 440 V/800 A High Temperature Superconducting Fault Current Limiter (SFCL)

The addition of new generation capacity, interconnections and expansion of power network could increase fault current levels beyond the capacity of the installed circuit breakers. Conventional solutions to limit the fault levels are not effective measures when reliability and stability of power system are considered. High temperature superconductor fault current limiters (SFCL) are intelligent and self acting devices that can detect and limit fault currents within a quarter of the first cycle and without adding additional reactive power to the system. The benefits of utilizing SFCL include ability to connect new generation stations to the electric system, avoiding upgradation of existing networks and increase of network flexibility, sustainability and reliability. In India, Ministry of Power has initiated a National Perspective Plan (NPP) for R&D in Indian Power Sector, jointly funded with industries and research organizations. Under the NPP project, CG Global R&D is developing 440 V, 800 A, resistive type SFCL in Phase-I and 11 kV, 1250 A SFCL in Phase II. This paper presents the development and experimental results of 440 V, 800 A resistive SFCL utilizing second generation (2G) high temperature superconductor (HTS) tapes. SFCL performance parameters like response time, limited current, prospective current, recovery time and cryogenics are discussed. The reported data would be useful in developing commercial scale SFCL for the power grids.