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A high temperature superconducting (HTS) power supply with YBCO coated conductor (CC) pancake load is developed. The pumping-current is measured with respect to the magnet flux changes by installing a hall sensor at the center of the YBCO CC pancake load.

A detect-and-activate-the-heater (DAH) protection technique is performed on the small coil wound with YBCO tape. In this DAH protection method a protection heater is activated to create an additional normal zone to absorb the stored magnetic energy enough for keeping the initially quenched zone from overheating.

The quench behavior of a test coil assembly consisting of Y[Ba.sub.2][Cu.sub.3][O.sub.7-[delta]] pancake coils is analyzed. An active protection scheme is designed and integrated to the test coil assembly.

Epoxy impregnation has improved thermal contact in a winding pack and has promoted normal zone propagation (NZP). Measurements with wet-spacers in which a large contact thermal resistance at each YBCO tape and spacer interface is responsible for very slow transverse NZP velocities have effectively eliminated the interface thermal resistance, resulting in faster transverse NZP speeds.

The development status of joint method between the superconducting YBCO coated conductors (YBCO CC) is described. The studies have shown that the removing process by heat has deteriorated the YBCO layer partially and the heat generated by over current has weakened the deteriorated spot.

The quench characteristics of stabilizer-free and copper-stabilized YBCO coated conductors (CCs) are described under various over-current pulses differing in waveform. The studies have provided a basis for the temperature design of various superconducting power applications including superconducting fault current limiter (SFCL).

An experimental method is described for determining the recovery of resistive superconducting fault current limiters (SFCLs). The thermal relaxation time needed for the temperature of coated conductor (CC) to decrease to 77 K is assessed.

The impedance in nominal current can be reduced by applying the non-inductive coil wound with two types of high temperature superconducting wire to SFCL. The magnetic field is applied to commute a fast switch in hybrid SCFL systems.

The properties of high temperature superconducting (HTS) persistent current switch for Maglev application are examined. Results suggest the observation of initial current decay when the initial charging current of persistent current mode (PCM) operation is higher than 50 percent of the critical current of the HTS magnet.

The recovery characteristics of superconducting fault current limiter (SFCL) with respect to applied voltage are examined in a power system. Results suggest that the recovery time is mainly dependent on the maximum temperature at the end of the fault and the material of the wire.

Electric method and calorimetric method were used for examining the transport current loss of the bifilar magnet using coated conductor. Findings reveal the reduction in the external magnetic field effect generated by the transport current.

The relationships between voltage per meter, temperatures and resistances of two different stabilizer materials were examined for the design of a 13.2 kV/630 A High Temperature Superconducting (HTS) fault current limiter (FCL) coil. Results suggest the use of thick stabilizer for increasing the voltage per meter.

The design and testing of superconducting fault current limiter (SFCL) wound with stainless steel-stabilized coated conductor are discussed. Results suggest the effective amelioration of the compactness in the fabrication of SFCL rated on larger capacity.

The design and testing of the 220 V/300 A class non-inductive winding superconducting fault current limiter (SFCL) are discussed. Findings reveal the observation of good current limiting characteristics of the SFCL at a distribute power source of 220 V with operating current of 300A.

The operational characteristics of a resistive non-inductive winding type based superconducting fault current limiter (SFCL) by using YBCO coated conductor are examined. Findings reveal 90.5 percent and 97.9 percent coincidences for the peak values in the first and last swings between the experiment and simulation results.

The over-current characteristics of coated conductor clad with various stabilizers are examined. Findings reveal that both-sided stabilizer is more desirable than one-side sand high and that resistive material is essential for the stabilizer.

The performance of a short-circuit test on non-inductively wound solenoid type superconducting fault current limiter (SFCL) is discussed. Results suggest that a shorter difference between the outer and inner tape is essential for more elaborate simulation.

The study presents the characteristics analysis of a high-[T.sub.c] persistent current system with double pancake magnet using coated conductor. The voltage generated in the load can be easily used for the determination of the characteristics of the initial current decay.

The analysis presents a joint method used between the superconducting [YBa.sub.2][Cu.sub.3][O.sub.y] (YBCO) coated conductors. The results show that the copper stabilizer can be easily delaminated by the heat contact with the soldering iron.

The characteristics analysis of a high-Tc superconducting power supply considering flux creep effect is described. The results suggest that the normal zone resistance and various inductances due to the time constant bring on the current saturation.