DEVELOPMENT OF THE PROSPECTIVE POWER TRANSMISSION MODEL SYSTEM INTEGRATED UNDER SUPERCONDUCTING ENVIRONMENT-PROMISE

A ''prospective power transmission model system integrated under superconducting environment'', abbreviated to the PROMISE, has been constructed to verify a technical possibility of superconducting power transmission for next generation. The PROMISE is composed of a superconducting transformer, a superconducting fault current limiter and superconducting power cable of length 5m. Three superconducting apparatuses are enclosed all together in a long scale cryostat to be kept at the liquid helium temperature of 4.2K. The major insulation is provided by liquid helium. The PROMISE withstands AC voltage of 6kV for 2 minutes with quite low partial discharge. A voltage-current synthetic test has proved that the PROMISE has the transmission capability of 6,000V-1,000kVA. The fault current limiter actually limits overcurrent and prevents the other apparatuses from quenching. Quench current level coordination is actually realized in the PROMISE.