I-V Characteristics, Minimum Quench Energy and Normal Zone Propagation Studies of forced flow gas cooled YBCO tape

Fundamental investigations on self-field I-V characteristics as well initial quench induced normal zone propagation characteristics of second generation YBCO coated conductor has been carried out in forced flow nitrogen gas cooling (77 K) condition that simulates practical applications. A special forced flow facility laboratory set-up was developed in order to characterize the coated conductor in laboratory. Normal zone in conductor is initiated by a heater element glued to the conductor surface. The minimum quench energy (MOE) and normal zone propagation velocity (NZPV) have been estimated by monitoring voltage and temperature evolution along the length of the conductor. The minimum quench energy (MOE) value has been evaluated for a particular transport current by varying the heater energy. The minimum quench energy and the normal zone propagation velocity in the YBCO conductor under the forced flow nitrogen gas cooled condition is experimentally estimated to be 0.393 kJ/cc and 0.33 cm/s respectively under self-field criterion.